In railway workshops it was common practice to strip everything off a loco, carry out an overhaul then rebuild the Loco.
As long as the parts were the same, then to save delaying the reassembly, any suitable overhauled part would be refitted to the loco.
In one particular case I was tasked with recording all the loco numbers that had been stamped into the wheels of an LMS 3F 0-6-0T loco that we were restoring. I found 45 different numbers in the 3 wheelsets.
I would think it quite likely that something similar would happen in an MOD Workshop.