Yeah, seems you have to turn off OB for OS update to work.
Upgrading from 1.11 beta to 1.11 and had the same issue.
Switching from Overbridge Mode to USB MIDI Only worked for me!
Hey! My DT was frozen too. I realised that it was connected in Overbridge mode [Usb Config Section]. It has to be set as Usb Midi only so the system can receive the syx file.