No. He's entitled to 'Forces Help to Buy' though. This is a loan (effectively interest free) and can be up to 50% of his salary (annual), up to a maximum of £25k. It's to be used to enter the property ladder, and has replaced the old LSAP (Long Service Advance of Pay) scheme.
Not quite! Paid off over 10 years yes (if you had sufficient time) but payments commenced 2 years after taking it regardless of how many years remaining left. If you took it with 10 years service or more then your repayment period was reduced.
Irrelevant now it's called something else - different rules!