I think it'd be beneficial for the fund and founders in general if you could fill out the latest version of the YC app anytime. It seems you already have draft functionality, why not keep this open and allow users to create draft applications throughout the year?
I personally use the application as a way to test out my understanding and boiling down communication of ideas. I understand and have copied all the questions to a doc and use that regularly, but theres something about filling out the application on YC that makes it different.
If you allowed founders to use this application as a sandbox for all their ideas, this data would be insanely valuable. Seeing multiple draft applications from someone would give indicators about thought process and more importantly progression. Not to mention a wider understanding of markets that entrepreneurs are thinking about.
Product of not being able to fill out the application for a side project, headed back to github.