Tried downloading/installed YOG4PASN0, device rebooted and still on old version

I tried OTA updating today to YOG4PASN0 and it downloaded/installed the upgrade. It rebooted into TWRP recovery. I rebooted it again and it was still on the old version of YNG1TAS2I3, still notifying me of YOG4PASN0 being available.