B can operate off container ships, or from desert oasis.
Even to a non-pilot like me, it is obvious there is more to operating from such "bases" than simply landing and taking off. I seem to recall a Harrier trying the first, but only in an emergency after a bird strike, or similar. The 2nd concept, a tactical land base, was in the original CONOPS for Sea Harrier and the necessary kit procured (e.g. Air/Land/Sea MADGE), but when AMSO suppliers decided to scrap it in about 1992 as a "savings" measure without mentioning it to the RN, the RN rolled over and said "It's ok, we didn't really want to do it anyway". A strange posture, given we were half way through the Mid Life Upgrade. We were shelling out big bucks for a fixed price modification contract and the kit was in the skip.
If this "oasis" concept was suddenly inserted, proper scrutiny would point out the previous waste and ask serious questions. Not that the chair of the Defence Select Committee would be interested in such scrutiny; after all, it's only his job.