Not to mention if a Sgt with 5 or so years to do is kept in against his will while a FS or Master with between 5 - 10 years to do is shown the door then again an employment lawyer would surely have a case.
After all it's not the fault of the FS/MAcr that the RAF/MoD/Government made a cock of the manning structure and ultimately they can all do the job that the desky is holding the Sgt for (on the off chance we have a maritime future).