I don't know the number for switching, but the AT&T Partner Affinity Office is 1-800-288-2662. They might know. The standard bonus is 5k, sometimes this doubles to 10k. That's about all I've seen.

BTW, I switched to AT&T on October 20, 1999. I still have not gotten my points. I've called AT&T every week for three months; my file with them is *SEVEN* pages long. It takes most agents ten minutes to read all the notes on my account. Every agent swears they will resolve the problem -- and every agent is completely useless. YMMV, but I'm going back to MCI.