Per the 5.0 SP1 upgrade guide on page 41 you can get most of what you're looking to do explained ... however there really is no clear explanation (which is disappointing).

That said, I would upgrade BAS first, then upgrade standby, and then lastly upgrade primary.

Attached Images

BlackBerry_Enterprise_Server_for_Microsoft_Exchange-Upgrade_Guide-T561574-819646-1029041635-001-.pdf (643.3 KB, 227 views)

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