Is it certain that 7 & 20 Bdes will be Armd on return? They may well end up as 7 & 20 Lt Bdes. Ergo no armour hangarage or access to SPTA required.
As for the carrier aircraft, somewhere near the carrier's home port. Since the Navy won't be able to justify Portsmouth AND Plymouth, they'll be down to Pompey and Faslane by then. So somewhere close to Pompey. Yeovilton or Odiham depending on who gets them.
Alternatively, no carriers means no carrier aircraft means no basing question.