I did that, weekly commuted as a singly, with a property elsewhere. He will get GYH based on mileage to the home residence, payable as a daily rate in his pay. Part of the accommodation charge is CILOCT which is a (small) contribution to council tax but he will still have to pay full council tax at the home address.
JSP 752 (Allowances) and JSP 754 (Pay and Charges) are available here:
RAF Community - Pay, Allowances & Pensions
SLA is about £5 per day, which equates to GYH for about 130 miles. So if he is 130 miles from home, GYH will just about equate to the accommodation charge. Food is PAYD on top of that, but then so it would be at home.