one thing you can do is call the Wing Duty Officer (stashed or attrited ENS, he has a direct veiw of the board with the class info on it. He may not know enough to give a time estimate, but he/she can tell you how many people are on it. THe more on it = the longer wait.
I was told there was a 0 wait when I left Penscola, got there and waited about 4 weeks. If things have not changed (bad assumption) marines were not having to wait as long since there were less of them and each class had to have some in it.