I hope you can keep submitting more than one quiz. You are lucky as I can only submit one quiz at a time and I have to wait 1 or 2 days before I can submit my next quiz. For me, I have to wait.
Seeing you were able to submit more than one quiz at a time, I think you should still be able to keep that featue as you obviously submitted excellent quizzes all the way through.
"Age is strictly a case of mind over matter. If you don't mind, it doesn't matter". By Jack Benny