Wife's Pixel began running battery down too quickly after Pi update. Stock, not rooted.
Upgraded Wify to Pixel3, reset Pixel to default, performed latest October 18 update gave it to Son. Son reports 100% to about 50% battery in just over an hour. Hope Google fixes this before they abandon Pixel updates (EOL).
I hope this isn't Google's kiss of death for the Pixel OG:
Google will guarantee software updates through October of 2018 (no guaranteed major updates after Oct18, Security updates should continue for another year).