From an admin's perspective does this mean touching every radio twice? The radio has the new profile and the old profile side-by side to make the switch easy for the troops. But can they then lockout or delete that old profile OTA? Or does everyone come in again to have that done?
Maybe I didn't explain enough in the last post...
Any radio purchased after ~2008 should have a "rebandable" firmware installed. Any radio older than that will be the only ones that should need a firmware upgrade.
Next: Depending on how the radio tech have the system set up...they might not even have to set up a new "personality" or system in the radio. There is an option in some radios to do a "spectrum search" over the band to find a new control channel (for the specific SysID). Older radios don't always have that, so may need a new list of channels that are possible control channels. Since the OKC control channel is legal (as far as I know) in the rebanding, little should need to be done.
When the system techs are ready to reband (all the subscriber radios have "rebandable" firmware), all they have to do is log into the system admin control and disable one of the >860 frequencies. Once disabled, the system will not try to send voice calls to that channel. They can replace/reprogram the site equipment (at all five sites) and tune it. Once they are happy with the reprogrammed/new equipment, they can "enable" it, and the system will start sending voice/data calls to the new repeater channel. They can do one or more channels at a time like this. The subscribers would have no idea this is going on (probably). The only downside is that one or more voice channels would be taken off-line, and the system could be busy. Another way around that would be to have separate (or new) equipment at the site, get it all ready, "enable" it, then disable the old equipment.
Basically, the firmware upgrade is the main things that the radio techs should have to perform on the subscriber radios. Other than that, they are like your scanner (in control-channel only mode) and will follow the voice channels where the system tells them to go.
Of course, I'm not a radio tech, but I would like to think I know a lot about how these system work (like other people on this board!).