The post-launch audit: What to validate in the first 30, 60, and 90 days after migration

Your migration didn't finish on launch day. It just stopped being watched.

That's the story behind most post-launch traffic dips. The team migrates, the homepage loads, someone sends the celebratory email, and everyone goes back to the work they postponed for six months. Three weeks later organic sessions are sliding, a screen reader user hits a barrier that wasn't there before, and nobody can say when it broke.

So I think we need to be clear about what launch actually is.

It's a transition point, not an endpoint. The site you shipped is now the site you have to prove works.

Siteimprove's analysis of enterprise migrations keeps surfacing the same failure mode: organizations treat the migration as a project with an end date instead of a transition into ongoing validation. Siteimprove's Post-Launch Validation Framework is the methodology built to close that gap. It's a recurring 30/60/90-day cadence that checks four domains at every phase: technical SEO health, accessibility regression, content quality, and measurement continuity.

It isn't the same thing as the launch-gate QA your team ran before go-live. That work tells you the site was ready to ship. This cadence tells you it's still holding up after it shipped.

Post-launch validation is a cadence, not a single pass

A post-launch website audit checklist works best as a cadence: three scheduled validation passes at 30, 60, and 90 days, each testing the same four domains for a different kind of failure.

Why three passes instead of one thorough audit? Because migration problems don't show up all at once. Some are visible the day you launch. Others appear only after search engines recrawl, after the content freeze lifts, or after a quarter of normal publishing has worn grooves into your new templates.

One audit catches one moment.

Here's Siteimprove's Post-Launch Validation Framework in a single view, with all three phases and all four domains together.

Each phase has one job. The first 30 days validate that technical SEO, accessibility, content, and analytics survived the migration intact. The 60-day check catches drift and reintroduced regressions once the launch freeze lifts and normal change resumes. The 90-day check confirms that quality and measurement are stable and sustainable, not merely restored.

Notice what repeats. The domains don't change between phases.

The question you're asking does.

One practical note before we get into the phases. Assign an owner to each domain before launch, not after it. On a decentralized estate, technical SEO, accessibility, content, and analytics usually sit with four different teams, and a cadence nobody owns is just a calendar reminder everyone dismisses.

The first 30 days confirm the migration didn't break the basics

The first 30 days of Siteimprove's Post-Launch Validation Framework exist to prove one thing: the migration preserved what already worked.

That sounds modest, but it isn't.

The most expensive post-launch failures look fine until somebody checks, and on an estate with tens of thousands of pages, nobody checks by accident. (I've yet to meet an editor who rereads migrated pages for fun.)

You also won't validate every page by hand in a month. So start where failure costs the most: your highest-traffic pages, your conversion paths, and every template that generates more than a handful of pages.

Start with technical SEO health. A redirect check verifies that every legacy URL in your mapping resolves to its intended destination in a single permanent hop. Not a chain, not a loop, and not a dead page returning a 200 status. A canonical check verifies that each page's canonical tag points to the live URL you want indexed, not a staging host or a retired path.

Then check for 404s and broken internal links, and look for orphans: pages that migrated fine but lost every internal link pointing to them. Confirm your new XML sitemap lists only live, canonical URLs and has been submitted in Search Console.

Google's site move guidance is worth rereading at this stage because it resets your expectations. Google says a medium-sized site can take a few weeks for most pages to move in its index, and larger sites can take longer. It also says the move happens URL by URL, and that Googlebot has to visit every URL on both the old and new site before the move counts as complete.

So on a large estate, your 30-day check is validating the start of the move, not the finish.

While you're in there, compare page performance on the new templates against your pre-launch numbers. A rebuilt template that adds a heavy script or an unoptimized hero image can quietly regress Core Web Vitals across every page that uses it.

Accessibility regression is next. It means a barrier that didn't exist on the old site now exists on the new one. New templates, rebuilt navigation, a component library that dropped focus states, a CMS import that stripped alt text: any of these can break pages that were compliant last month. Validate against the same standard you held before launch, which for most enterprises is WCAG. If you're a federal agency or you sell to one, the Section 508 testing baseline gives you a repeatable test set to validate against.

Content quality is the domain teams skip because it feels subjective. It's not. You're checking accuracy, completeness, and consistency. Did the body copy come across whole, or did tables, footnotes, embedded media, and downloadable documents fall out along the way? Did each page land in the right place in your new taxonomy?

Then measurement continuity, which has three parts. Tag parity means every tag on the old site has a working equivalent on the new one. Event integrity means your events fire with the same names and parameters your reports expect. Historical data retention means you can still compare before and after.

This one has a hard deadline built in.

Data you didn't collect in week one is gone, and you can't backfill it later. If you're running GA4, check your key events against Google's GA4 setup steps before you trust any post-launch trend line.

When a check fails, fix the template before you fix the page. A missing alt attribute or a broken canonical on one page is usually a symptom of the component that built it. Patch the page and you've fixed one URL. Patch the template and you've fixed every URL it generates, including the ones your publishers haven't created yet.

At 60 days, drift and reintroduced regressions start to show

The 60-day phase of Siteimprove's Post-Launch Validation Framework does two things. It catches the drift that starts once normal change resumes, and it confirms that the fixes you made in the first 30 days actually held.

By day 60 the launch freeze is over. Your content teams are publishing again, developers are shipping fixes, and marketing has spun up new campaign pages. That's healthy.

It's also exactly how post-migration regressions creep back in.

Metadata and taxonomy drift is the signature problem here. New pages get built by cloning an existing one, so title tags duplicate. Meta descriptions go blank because the field moved in the new CMS and nobody told the regional editors. Category tags get applied inconsistently because the new taxonomy is three weeks old and half your publishers are still working from memory of the old one.

None of these break the site, but they erode it.

We tend to file drift under content problems. I'd argue it's really a process problem. Your publishing workflow on the new platform is still settling, your editors are still learning where fields live, and every workaround they invent becomes a pattern someone else copies.

Revalidate accessibility too, and do it at the component level. A fix applied to one page doesn't fix the template that produced the problem. If your developers patched a form during the first 30 days but the underlying component didn't change, every new page built from it reintroduces the barrier.

You'll find it at 60 days or you'll find it in a complaint.

Content quality shifts from migration fidelity to freshness. Is the content you've added or updated since launch accurate? Are pages that were flagged for retirement still live and still being indexed?

On measurement, check that the tracking you validated at 30 days survived a month of normal change. New pages without tags, a consent banner update that suppresses events, a campaign landing page built outside your tag management setup: each one punches a small hole in your data.

This is also when recrawl results give you real evidence. Check index coverage in Search Console against your URL mapping. If legacy URLs are still indexed or new URLs aren't, you've got a redirect or canonical problem the 30-day check couldn't see yet.

The 90-day check proves quality holds as the site matures

In Siteimprove's Post-Launch Validation Framework, the 90-day phase confirms that quality and measurement are stable, not just restored. That's a different claim from the one the 30-day check makes.

At 30 days you proved nothing broke, but at 90 days you're proving three months of normal operation didn't break it either.

Technical SEO at this stage is about persistence. Are the redirects still in place, or did someone clean up the redirect map because it looked messy? Google recommends keeping permanent redirects live for at least a year after a move, and that's easy to forget once the project team disbands. Check canonical configuration and internal link integrity across the whole estate, not a sample.

Accessibility at 90 days asks whether your standards are holding as the site matures. By now the site has new content from dozens of authors, new components from at least one sprint, and probably a vendor integration nobody mentioned during planning. Each is a fresh opportunity for regression.

Content quality now connects to business goals. Is the content the business expected to perform actually performing? Are the pages that matter most accurate, current, and findable?

Measurement continuity at 90 days is about reporting accuracy. Can your leadership dashboards compare this quarter with the same quarter last year in a way you'd defend in a budget meeting? If not, you've got a continuity gap that will undermine every claim you make about whether the migration succeeded.

So what does a passing 90-day check look like? Not zero issues. I've never seen an estate of any size with zero issues, and I doubt you have either. It looks like a known, stable issue rate that someone is watching, with no domain trending in the wrong direction.

Here's the part we tend to miss.

The 90-day check isn't the end of the cadence. It's the point where validation shifts from recovery to routine, and the baselines you confirm here become the standard your ongoing monitoring measures against.

Silent decay, not launch-day bugs, is the enterprise risk

Launch-day bugs are the easy part. Everyone's watching, everyone's motivated, and the war room is still open.

The risk is the decay nobody flags.

Redirect and canonical decay starts when someone edits the redirect map months after launch, or when a new section gets built with canonical tags copied from a template that points somewhere else. Accessibility regressions get reintroduced by ordinary content and code changes, one component at a time. Metadata and taxonomy drift as publishers improvise. Analytics continuity breaks when a tag gets dropped from a new template and nobody notices because the dashboard still shows numbers.

Every one of these patterns surfaces on a delay.

That's why a launch-day checklist misses them and a recurring cadence catches them.

These patterns also aren't random. They map to four categories in Siteimprove's Enterprise Redesign and Migration Risk Framework: Performance and Discoverability Risk, Accessibility and Compliance Risk, Content Risk, and Measurement Risk. The post-launch window is where all four compound at once, because the team that understood the migration has moved on and the team that inherited the site doesn't always know what to look for.

I'm not going to hand you an incidence rate for any of this. Reliable public data on how often each pattern occurs after enterprise migrations is thin, and you should be skeptical of anyone quoting precise figures.

But you don't need a statistic to see the mechanism. If decay arrives on a delay, validation has to arrive on a schedule.

I'd rather see a team run three modest checks on time than one exhaustive audit nobody ever repeats.

Post-launch validation begins where launch-gate QA leaves off

Siteimprove's Enterprise Migration QA Framework gates the launch. Siteimprove's Post-Launch Validation Framework governs the weeks after it.

The QA framework is the validation gate that spans the launch event itself, with pre-launch, launch-day, and post-launch stages. Its job is to answer one question: is this site ready to go live, and did it go live correctly?

The post-launch cadence picks up from there. It's a temporal cadence that governs the weeks after launch, and it answers a different question: is the site still working?

The two are complementary, not redundant. The QA framework ends at the handoff, and the post-launch cadence is what happens after it.

Here's why the distinction matters. When you conflate them, the post-launch stage of QA becomes the last check anyone runs. The QA team signs off, the project closes, and the weeks after go-live go ungoverned.

That's exactly when redirect decay, accessibility regression, and analytics gaps show up.

Siteimprove.ai is the visibility layer, not the remediation service

A validation cadence is only as good as the evidence behind it. Manual spot checks across tens of thousands of pages don't scale, and sampling is how silent decay stays silent.

Enterprise teams running this cadence need systematic monitoring that catches regressions as they emerge, not weeks after the fact. That's the role Siteimprove.ai plays. It's the ongoing visibility and evidence layer: continuous crawling surfaces redirect failures, canonical errors, broken internal links, missing metadata, and accessibility regression across your estate, so your team validates against evidence instead of a sample.

That changes what each phase of the cadence looks like in practice. Instead of rebuilding a picture of the site every 30 days, you're reading a trend. Is the issue count in each domain moving the right way, and did the fixes from the last phase stick?

Be clear about what it isn't. Siteimprove.ai isn't an agency, a consultancy, or a remediation service, and it doesn't run your audit for you. Your team owns the cadence, the decisions, and the fixes.

The platform makes the problems visible.

One more boundary I want to state plainly. Accessibility checks surface structural issues like heading hierarchy, missing alt text, and semantic markup, and those same structural properties matter to how search engines and answer engines parse your content. That's a shared structural input. But it isn't a proven causal path from accessibility scores to AI citation, and you shouldn't read it as one.

Take away

Launch is the moment your site stops being a project and starts being your responsibility.

Check it at 30 days, check it again at 60, prove it at 90. Rinse and repeat.