My understanding of it was not that the entire OCC class would be female in the sense that it would be some abnormally huge female OCC class, but rather that it would be the PLC guys and girls that make up for the normal male OCC slots because they can only go in the summer since they are in school and OCC guys can go whenever and they are filling up. OCC is already the most competetive program, so they can do what they like and still fill up OCC classes. What's more, there are rumors of just preselecting all OCC people a class ahead to have a better idea of future classes.
Personally, I think the attrition rate thing is all that matters from 191, which unless I am mistaken the winter OCC has the highest average attrition rates of all the classes, generally speaking - since you really can't say for sure. In the end, the best explanation I have heard is that they really don't know until the quotas our out how many slots there will be are out and there has not been a denial of an OCC summer class yet, although that might depend on contract. Lastly, you must bear in mind OSOs could hypothetically insinuate to people who come in early in the fall that they should apply to the winter class because there is no summer class and he/she could not go again 'till fall, in order to fill up slots in the first fiscal year OCC class (winter).
This is all speculation and rumor gathering on my part though.
S/F