The UAS will treat you as what you'll be, an RAF volunteer reserve officer cadet - adventurous training, officer training, and flying training. The PPL will be taken as a sign that you're serious about aviation, and whilst you'll go through all of the syllabus you can expect to go through the first chunk very very quickly and probably be on aeros within a few sorties.
The aircraft are military assets shared between the UAS and AEF organisations - there will be absolutely no opportunity for you to hire them privately.
Apologies for getting your gender wrong. When I was a university lecturer, one of my best students (and also a very good pilot according to the OC of her UAS) was also a she, so I should know better.
G