If anyone should pre-board it is United Club Members. THat way you could actually use the Club right up until time of boarding. Otherwise you end up at the end of BG1- not awful, but not great depending on the flight. And also, if there are delays, it's nice to be able to go back to the Club to chill or work on alternatives. I'd rather see UC members get pre-boarh than 1Ks. And I am both.