Taken Directly from the Admin instruction for FRI 3:
Notice to Terminate/Optional Exit Point
14. An individual who has received a FRI payment will be expected to complete the RoS requirement. An application for Early Termination or to exercise an option point will not be granted until such time that the RoS is satisfied. In the exceptional event that they are permitted to leave the Service during the RoS period they will have to repay the net value of the FRI on or before their last day of service. Compassionate cases, including medical cases, will be assessed on a case-by-case basis by Service Personnel and Veterans Agency Joint Personnel Administrative Centre, Pay & Allowance Casework Cell (Glasgow) (Recoveries and Write-Offs) (SPVA JPAC PACC (G) (R&WO) with casework advice from ACOS Manning.
If you are not happy with that, then don't take the FRI....It's as the meerkat says in the advert.
Regards
TEP
