Interesting ... as this was told me by a UA phone res agent, it has to be taken with a grain of salt, of course. But if I had gone ahead and booked--the sole reason I didn't was that I wanted a paid ticket, the cert for fiancee, and paid DCA-ORD-SAV was $600 at the time--as the agent was willing to do, I wonder if at some point UA would have refused to accept the cert? Hmm.