Just incase anybody else is looking for an answer in the future.
I asked the recruitment officer at my TA squadron about this situation, although he's not 100% of the maximum age for entry and training
(he also said call MW for a up to date answer). He said that after graduating from Sandhurst as an officer that can't be taken away
(unless you're really silly), so joining the Regulars / AAC as an officer would only require a bridging course.
I'll update the thread when I hear more from Middle Wallop
Thanks guys.