Hi, a good guide here on producing sclerotia/truffles and fruiting the Psilocybe species that produce them. In this guide it recommends leaving one's jars for two months at least following colonisation, but one can leave them for longer. I've heard of people reporting greater potency when harvesting at 3-4 months. The general consensus I've got from mycological forums is that longer substrate incubation times will increase potency. It sounds like your jars could be at optimal harvesting time from what I've read so far. I have some P. galindoi jars (with a substrate of whole oats) that are around the same age that I can see are producing ample sclerotia...I will be fruiting them first though as my main interest is the mushrooms.
http://en.psilosophy.inf...l#harvesting_the_stones
Like the P. cubensis strains, there is lots of hyping up of sclerotia "strains" by vendors for marketing. Any sclerotia will be produced by P. galindoi. P. mexicana or P. tampanensis...although according to some recent genetic research, there are actually all regional substrain variants of P. mexicana.
I think the sclerotia will dry out fine in a food dehydrator whole, unless they are unusually large chunks.