Electric Zoo already has a pretty big claim over this for the end of summer romps, and the 2013 Governors Ball just finished there as well. With that said, that really only leaves July as a potential timeslot for Mysteryland, but have you been outside on Randall's Island during a July heatwave? I have and I don't wish that upon my worst enemy. That heat is murderous and is the sort of thing that'll send anyone over the deep end and the number of molly overdoses skyrocketing. An idea, but not the wisest one.