The latest security update of February might have broke something related to Bluetooth files in the Google Pixel and Pixel XL, apparently causing the Bluetooth to turn off automatically without any signs, however, it can be turned on manually again, but that's annoying.
After numerous reports submitted by Pixel Users , Google has now acknowledged the issue and is said to be working on the fix.
Thank you all for your detailed feedback, and to those that submitted bug reports. It has been extremely helpful. The team has identified a fix, and it will be rolling out in an upcoming release. I'll keep you all posted with any other details!
We expect Google to release Bluetooth Bug fix update along with March's Security Patch.