when to mail check?

It would probably be more beneficial if they already have your money when they do receive your application. For schools that have the just-send-us-some-money policy, consider it another item you need before your file is complete (no money, no application review).

Schools I paid early seemed on top of things and acknowledged payment without my application. I was worried my check would just get lost in a pile or something.

 

Absolutely! I sent out most of my checks the day after I pressed that orange "submit" button. Oregon has already processed my payment and sent a receipt. It seems AADSAS will be doing the first mailings starting tomorrow (June 23). At least that's what the site is telling me. So get those payments in tomorrow and you should be good.