For a while, I couldn't get it to work. Dialed my B1 channel and the modem started buzzing. Okay, so we had the right number. Fortunately, Homer's brother Garrfield was on hand. He played around with it and managed to connect. This let me download my mail. Then some more playing around with the "bap" and finally, everything okay, with B1 and B2 together again.
So. Phone service again. Sort of.