There is a "priority" lane at the BWI security area that leads to the D/E concourses (where the UA gates are), but it's not marked "premier access" because it includes priority for all airlines with gates in D/E (Delta, international, etc.). Unfortunately you kinda have to know what you're looking for, but there is definitely something separate.
All of that said, the only times I've been traveling with someone who used it that line is just as long as the regular non-priority security line. Not sure what Thanksgiving weekend looks like though.