BT were absolutely appalling for us when we moved house. Phone and Broadband problems.
The one key problem is their Indian call centres. If you have a slightly convoluted problem it is impossible to make yourself understood.
They have a script and if your problem isn’t on there you’ve had it.
We eventually got handed on to the “Special Care” Customer Service Team in Rugby or somewhere. They were great.
However, you’re only allowed to call them for 30 days after the problem has been resolved. Then you’re back to the appalling service of the overseas call centres.
I would make the move in an instant to ANY company that guarantees UK call centres for all their services.