It's weird. I think in my state, the application deadline is actually after the ELSES exam reigstration.
I think the state deadline was 60 days, but I had to register with ELSES by the end of January, with my approved state app in hand.
Regarding re-studying in the event of failing, I don't think you would need as much time the second time around.
You can spend less time on what you did well (per the diagnostic report), and if you've kept your references and personal notes in order, you can just dive back in.
I've got 3 loose-leaf binders full of hand written study notes and applicable tables/regulations I printed off the web that wasbasically my own personal conslidated reference manual.