When I worked for the RFDS WA Section many moons ago, I think we had 4 or 5 bases other than Jandakot. Of the 5 they have now only Meka and the Port are the same. Some of the others were covered by the Goldfields section and pretty sure Broome came under the Victorian section back then.
So for much of the RFDS operational history shows they operate from bases - so when a new type is implemented, I don't see why the operation now should operate from a single base when using multiple bases has proved effective.