It has been reported by Moz that over the last 2 weeks, the number of Mobile-friendly tagged websites on page 1 of search results has increased from 66.3% to 70.1%. Although, there are two possible explanations for this trend:
- Google's Mobile-friendly update has been slowly rolling out over a couple weeks
- Universally, webmasters have been preparing their sites for the April 21st deadline
Google previously stated that the algorithm changes could take days or weeks to fully manifest themselves, so it's not a surprise that we didn't see drastic changes after just one day.