So, the BES I inherited was running on an old server that was ready for a new purpose. I had a nice new Hyper-V based VM ready to host BES services, but there were a couple steps I had to take to get the services there. I was not wanting to make a knife-edge switch, as I wanted to do this a few users at a time. I only have one SRP Identifier, and my support is currently through Sprint, not RIM. Here is the solution I came up with that worked out quite well.
1. Move the database (optional)
The BES was using MSDE on the local server. Since I was decommissioning the local server, this had to move. I migrated from MSDE to an existing SQL 2005 DB. Here is an article for reference: KB12247 on http://www.blackberry.com/btsc/microsites/microsite.do
2. Register with Blackberry/RIM for a trial BES license
You have to sign up and give them a valid email address, but once approved, you get a trial SRP ID. This is required if you want to run your new BES in parallel with the existing BES. As of the time of this posting, you can request a trial here: http://na.blackberry.com/eng/services/server/offers.jsp
3. Load your new BES, use the production DB and Trial SRP
Build the new BES (it should be in the ballpark of your production version). You should be able to point the new BES to your shared DB and manage it alongside your existing BES. Make sure you use the new SRP-ID so that you don't lock your existing SRP. Having these in parallel allows for a much easier migration.
4. Move users
Right-click, move user (you can highlight multiple users if you want to do batches). This will do a seamless OTA migration of the user. You should look at the last contact on the device though, because if it can't find them, your new BES will log an error quite frequently as it attempts to contact and migrate the device.
5. Decommission old BES
Uninstall/Disable services. Remove from Management GUI.
6. Replace temporary SRP with production SRP using Management GUI.
Now you can go back to your original SRP. You are now running on the new server.
This process worked for me. Let me know your experiences.