I have a new Ex2007 server to begin migration from Ex2003 server.

All is up and running well. Have a BES v4.1 and about 50 Blackberry's.

Questions:
Do I move all the BES users at once and move the BES over to the EX2007 server ?

If I pick and choose what users to move, what do I do with the BES ? Leave it with the Ex2003 ESM until all are moved ?

When do I move the MAPI account to Ex20007 ?

I have some thoughts and all docs from RIM on the actual move to EX2007 but nothing I can find on the phased migration and the place for the BES server...

Thanks in advance.

Ron