Thanks guys. I realise it might work -most times, but, 1. it's a gamble, 2. customer wants to be assured of constant good service (at least feel like he has this)3. after all the hassle with AT&T about this it would be better business for me to just move it, and 4, customer is a lawyer and is irate at AT&T.
I have a new sub who is PRI experienced. If he knows how, is there any legal reason why we can't just move it ourselves? If absolutely necessary I can probably get a release from AT&t. I'm sure they would be glad to get customer off their back.