I try to get to my gate about 15 minutes prior to when I estimate boarding will begin. During this waiting period, I often see a gate agent walk up to the sign that says Priority AAccess / General Boarding and flip it around, to switch which lane is which. (Usually that also makes the signs not match the tape colors.) I asked a gate agent once why he did so, but didn't get an answer (he said something like "Sometimes she likes to do that"). Anyone know?