Google seems to have made a switch a few days ago where on mobile search they are now likely to serve featured snippets from pages that are powered by AMP. @thefke and @glenngabe were one of the first to notice this and I am able to replicate it.
For example, if you search for [how to use twitter] on Google desktop vs Google mobile, you will get Wired’s non-AMP page for the featured snippet on desktop and Forbes AMP page for mobile results.

Some publishers and webmasters are noticing significant changes in their traffic because of this change. It seems, although Google has not confirmed this yet, that Google may prioritize an AMP document in the mobile featured snippets over even mobile-friendly pages that are featured on desktop.
This is not always the case, I was able to bring up results in the featured snippets box on mobile that were not powered by AMP.
Do you see this as well? Has your Google traffic for featured snippets changed in the past few days?
Forum discussion at Twitter.

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