Hi Emily yes once you upload it before June 8 then you are fine. I had lots of issues dealing with that back in March, 2 months ago so I mailed it to them and they had no issues receiving it. It was attached to my file right away.
And you are right they can take a very long time to respond in web form that's why I decided to mail it instead but you can do whatever you feel is best for you.
Within one week of them getting my Schedule A, my background check started.
Awesome! Thanks for this... Im just stressed out and dont want to make a mistake and i know im not the only one haha... Thanks again!