Pre-shed soaking?

[Norm66]

My JCP, Jerome, has been soaking in his water dish for the past couple days. When I bought him I remember the breeder saying he would be due for a shed fairly soon so I'm assuming that's what this is.

I know it can be a sign of mites, but I've never seen any and he's been home for 3 weeks and just started this behavior, I would think if it was mites he'd have been doing this from the start.

So my real question is how long might this go on and should I be worried that he's on the cool side in water for extended periods? It's 78-80 deg F on the floor of the cool side depending on what time of day it is.

Thanks.