FC is not necessarily a ground branch. A considerable number are employed on flying duties.
What is your main reason for wanting FC? Is it to be operational and associated with aircrew? If so, and you do not get a flying slot, you may well find yourself limited to telecom association.
Have you thought about becoming an ATCO? The jobs are not a hundred miles apart. You will probably have a bigger chance of expeditionary deployment.
Both jobs require aptitudes very similar to aircrew. Essentially if you were to fail pilot your chances on the others would not be high. FC is possibly the most demanding non-aircrew job with an historically high failure rate. What is your fall back position?