Haven't flown Continential in ages. This time I am using an upgrade. So we fly the long legs to BON in B instead of steerage. The first and last legs of the trip, DCA-EWR and returning IAH-DCA, are in U, because there are no other classes on the short hops.

Can I still use the First-class check-in and lounge at DCA, and the lounge at IAH? Or am I a peon because one leg of each trip is in U?