Nomad, the weather here is ok now. I have some odd shifts this week so not sure I will get to the pool but I have 2 weeks off after so I will definately be getting there then!
Not sure Taz - according to my mate 2 mins if it's going on skin but no more than 3 mins if heating bed. Before reheating make sure bag is back at room temp. Apparently instructions say put a small dish of water in with it but she finds the steamy atmosphere makes the bag damp x