Google shared some data around the aftermath of launching its Google Speed Update officially in July 2018. After Google giving site owners notice of the update in January of 2018, Google saw that that the slowest one-third of traffic had performance metrics improve by 15% to 20% in 2018. In contrast, it saw zero improvements in 2017.
Google has posted a warning in the Google Search Console data anomalies page that you can expect those reports to see an increase in the number of issues and affected items and/or pages starting on April 3, 2019. The reason is Google has started to collect data from more pages than it previously did.
It looks like Google is testing showing a new type of image thumbnail in the mobile search results snippets. Some pages that have AMP Stories are seeing that their snippets in the Google mobile search have images showing off that there is an AMP Story available to be clicked on. AMP Stories launched over a year ago to provide visually rich and interactive content in an AMP format.