Tonight at IAD tried to get myself protected on a later flight after my original flight went MX with a decision time 1 1/2 hrs in the future. Since my flight was departing from D26, I went to the nearest customer service desk next to gate D7. No line, just three agents talking. Explained what I wanted. Agent looks at my flight, determines the two later flights are sold out, and tells me to go to the C20 customer service counter since "this one is just for UX" and "they are more familiar with mainline flights". I am a 1K and she saw my 1K BP. Smells like work avoidance to me, or is it real true that the only CS desk in D is only for UAX and the agents can't protect someone on a future UA flight? (I'd assume the process is 100% identical whether UA or UAX). But before I send a scathing email to 1K Voice I figured I'd ask folks here who are more familiar with IAD. Instead of hiking all the way to C20 I called the 1K desk and got it taken care of in 3 mins.