Just a little more insight - this is because the EUA system runs via computer where as the waitlist requires user intervention. i.e. if no agent happens to look at availability after seats are dumped into F and before EUA runs, EUA will go ahead and pull the seats at the designated time. It sucks but you have ot alert an agent to process your waitlist request before the EUA process it's list.

A great enhancement of having two upgrade lists.