More than One Submission at a time?

I've submitted my serial Juryokine for review, but I have three others that I'd like to get reviews on as well. So far I've held back because I figured there might be some unspoken rule (or spoken, and I just didn't see it) about submitting more than one story at a time and filling the board with my requests.

There's no rule about that, written or unwritten.