Another option is to flip. Do the desert as soon as you arrive in May - that would still be warm/hot, but early morning and evening hiking would work. Then do the sky islands, then the plateau. But, since we're a short trail (compared to the Triple), that's a lot of shuttling for an 800 mile hike. Better to do it as a thru-hike when you can hit the spring or fall prime season. But I wouldn't recommend a thru-hike that starts that late. Takes the joy, and safety, right out of the hike.