Google is Rooling out an Update on 21st of April and the Information we got is for Mobile Friendly Websites.
R U Mobile Friendly??
If Yes.. Have you did the Mobile Friendly Test (Search:: google mobile friendly tool)
If you're not mobile friendly. Please Make your Blog/Website Mobile friendly.
Effects of Update.
Well We Don't Know untill update is completed and may be many big websites/blog will suffer from the Update.
Hope You will be on safe side of Update (Mobile friendly).