The update, which includes fixes for a number of issues affecting Pixel devices, was first pushed out Monday. But, a day later, Google lists the Pixel 4 version of the release as available for all carriers "except AT&T."
The company hasn't officially commented on why it pulled its software for AT&T, but Reddit users have reported that Google Pay no longer functions following the update. According to 9to5Google the source of the problem is that Google didn't properly certify the build for AT&T. If that's the case, it's likely that other apps will also run into issues, though Google Pay is the only major one that's been reported so far. The good news for Pixel owners, at least, is that it should be a relatively easy fix, but no word yet on when the updated update might drop.