Nick,
I don't know if this will be of any help and I certainly don't wish to get your hopes up unnecessarily but some 8 years back (after leaving HMF) I required surgery for a cervical spine condition that was not life threatening but needed asap to avoid further possible complications. I was told that it would probably take a year or so. Then I found out about a little known article of protocol that ex-service personnel are entitled to go straight to the top of any NHS waiting list. I was sorted within a couple of months.
I realise you are still serving but if you contact the Veterans Agency maybe a similar protocol exists for serving personnel.
I hope everything goes all right for you.
All the best,
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