Nothing to see here, move along
Xboxen(hardware revision number)=Xboxen(hardware revision number)
It's not like there are thousands or indeed millions of every so slightly different computers to update. Any of which, may have components from manufacturers that don't entirely follow industry standards.
No, this is a console with rigid control over the BOM and thus the hardware inside each revision of the device. So, it should be a completely sucessful and flawless update.