If you've recently made changes to a page, and you notice that the associated AMP page doesn't reflect the exact same information, but instead shows old information, this is likely due to Google's AMP cache.

Outdated information can occur if both of the following occur:

• You are viewing a page directly from Google search results
• Google has not yet re-crawled that page since you made your updates

As mentioned, Google caches the AMP pages that it indexes in search results.  When Google crawls your site, they cache and index your AMP pages.  The next time Google crawls that page, they update the AMP cache with the new information.  For most sites that are frequently crawled, this can take less than a day.  For other sites who are less frequently crawled, this process can take longer.

To understand when and how often Google crawls your pages, you can use Google Search Console.  By clicking the "Coverage" tab, in Google Search Console, you can search for a page within this "Coverage" tab.  After searching, you will notice a "Last crawled at" column, which shows when Google last crawled this page.

Once Google crawls your page again, they will update the AMP cache, and you will see new information when coming form the Google Search Results page.

For any page accessed outside of the AMP cache, your content should be updated immediately after viewing the page.  For example, if you land on an AMP page anywhere outside of Google Search Results, you should see the recent, updated information.