The swap went well and quickly. When I set each device to do the enterprise activation, I was warned the phone would be wiped and rebooted. I approved that on each phone and they went to it. Shortly thereafter I reset each user at the BES to authenticate and run the enterprise activation on each phone. Yes enterprise activation was run twice on each phone, but what really happened was the first run through merely went into the wipe process. The enterprise activation went fine and everything was working as it should.
I then called CS at ATT and had them swap the phone number to IEMI listing they had. That was more of a formality than anything, as calls and data were working properly.
Done. No big deal, but figured I would follow up in case anyone else was going to do this.