Seriously though, you CAN attend Training but voluntarily forego pay. It's called C1 trg which means that you are covered for injury (on duty), travel at public expense etc. C/2 Means that it is of limited value and you don't get travel (unless it's to Rifle Assn Meeting). in all cases it should be noted in the attendance sheet exactly what class of Trg you are undertaking. TA Regs 1978 (Amdt 35), Chpater 2 Annex B/2 refers.
So, if you have rocked up to the TA Centre for 2 weeks work and it was on C/1 or C/2 Trg, you ain't got a leg to stand on and Her Majesty thanks you for it.