This started happening to me today (14 APR 2019) and I bought my Surface Pro 4 on 1 JUN 2016. I'm about 2 weeks and 2 days from being outside the replacement window! Good thing a quick google search led me to this page and a bunch of others letting me know this is a common problem. I've contacted Microsoft and a free replacement is on the way (as soon as I ship this one back using their shipping label). I'm not super happy that it is a refurbished one, but I guess that's better than this one that will be out of the replacement window in a few weeks.
Mine is a Surface Pro 4 with Intel i5-6300U and 8GB RAM running Win 10 Pro (version 1803). It's been plugged in and on for the past few days with minimal/sporadic usage. I've made sure everything was up-to-date, did a restart, adjusted display properties, reinstalled drivers, and ran the surface diagnostic tool, but no fix.
Flicker Video: https://youtu.be/jAVOQlg6Jmg
The best work around I've found is to have the taskbar clock display the seconds through a simple registry tweak. Google it!