IOS 16.0.3 Update has bricked 2 iPhone

Hi, has anyone had issues updating to IOS 16.0.3 from 15.x? We've had an iPhone 12 on EE and and old iPhone 8 (which was being used without a SIM card as an iPod in the Car), and both have been bricked by this update. The iPhone 12 failed to update through WiFi, and attempts to restore it (through Apple Support and iTunes) have failed miserably. The iPhone 8 was being setup to be used as a backup phone for the iPhone 12, but in order to restore the backup I needed to upgrade the phone to IOS 16.0.3. This was being done through iTunes. That also failed, and even putting the phone into recovery mode and trying to restore has not worked. To say that I'm angry is an understatement - 2 iPhones in perfect working order running 15.x have now failed completely to the point they are little more use than paperweights. On the positive side, the iPhone 12 is going to be repaired under the Carrier warranty, but there's no such warranty on the iPhone 8.

Anyone got any ideas about how to get my iPhone 8 back short of paying Apple hundreds of GBP to fix an issue caused by their software update?