Version CUCM 7.1(5), our IP phones are deployed without DHCP, all phone IP and CM information is configured statically. In the near future we will be changing over to a new Call Manager (version 8 or 9 not sure which) which will have different IP address/subnet. The current CM address was entered statically as the phones were deployed, but is it possible(or necessary) to rehome to the new CM address without going to each physical location and changing the address statically?
Other than using any of the 3rd party apps to control the phones remotely, yes, you'll need to change this directly on the phone.
I'm not even sure if there's a way to automate this via some SDK, you would need to check that in the developers forum.
if this helps, please rate