Crow-bag is right, 5 days, though you could wangle up to 10.
JSP 760 Ch8 said:
INTRA-THEATRE MOVES8.004 Trained strength personnel after joining their first unit, and those personnel completing Phase 2 and 3 training courses with a duration of six months or more, are to be granted 5 working days Relocation Leave for normal moves. This may be extended to up to 10 days by Commanding Officers, who are to take into account single Service guidance , unit manpower liability and the needs of the individual. One days Relocation Leave is to be granted for local moves.QUALIFYING MOVE 8.005 Normal moves are those resulting from an assignment order normally necessitating a change of SFA, SLA, substitute equivalents, Residence at Work Address or Selected Place of Residence (as defined in JSP 752 Tri-Service Regulations for Allowances). Local moves are those normally within the same establishment between SLA, or between units when no change of accommodation is required. Further advice, if required, should be sought from single Services.