I normally go in July/August and I find the heat and humidity combination oppressive. Thank goodness for your ebike then and I’ll be interested to hear how it copes with the heat.
Which part of Virginia you from? I normally do a trip there each year (from Australia) but have never been MTBing there. How do you go with the little monsters that lurk in your woods everywhere and suck your blood? Maybe the extra speed of the ebike will assist in keeping them off!