I've got an overseas purchased OnePlus 5 and SIM with Coles (Optus).
Applied the fix to enable VOLTE on phone but not sure it's working as there's no symbols next to the signal strength. (Although I can confirm I can access internet during a call.)
Still getting messages from Coles about the 3G shutdown and that device is affected.
Is anyone else in a similar situation?
Device shut down will be done based on tac code, regardless of and updates to the firmware.