Seo
How do I know if website changes improved SEO?
Compare the page's clicks, impressions, CTR, and average position before and after the change, using the same query or page group when possible.

A more useful answer
Use the same date range length on both sides of the publish date. A weekend or holiday can fake a drop.
Also watch form submissions from that page. A better ranking that creates no requests is not a win.
What to do next
- 01Save baseline metrics before publishing.
- 02Wait for enough Search Console data after the update.
- 03Judge by trend and conversions, not one-day movement.