Doesn't surprise me about AT&T, they are getting out of the residential and small business world, they just want big customers, too bad used to be a good company.
As far as your vendor goes (gotta raise my rates $100 and hour?) If BS matches your signaling it shouldn't be necessary, just a matter of swinging your service from the AT&T switch to the Bell switch. Having said that if they want your vendor on site it tells me they aren't real sure about what they are doing. We used to switch service all the time, all you needed is what the customer switch needs for signaling and of course the framing and line coding. There are exceptions to every rule, but most pure voice T-1's are D4/AMI, I think by other post you have determined that.
Bill
