you could , however (in my opinion) even if you manage to keep them for next years race season , they wont win many cards . due to fatigue of training during a Winter . Would be best to train them now , even if they are moulting , some short 5 milers , and 10.15 .or 20 milers in September when still mild would do. make sure they are flying well and fit at home first , good luck.