Heard a talk recently from the top man in Glasgow about reserve call up policy.
The clear indication was that regular reservists called up for Telic had less chance of getting through mobilisation than TA soldiers. As such, under 'Intelligent Mobilisation', it makes most sense not to rely on calling up 9 reg reserves to actually mobilise one man. However, if its your skills that are needed then the envelope will be on its way... the TA don't train many AH pilots from scratch for example!
That said - unless you've completely recovered from whatever your MD related to - you can't go without passing the medical.