The earlier you can get there, the better. Our YM and YW always try to get there before 5 p.m.; it seemed like it started getting lots busier around 5. (We go on Wednesdays.)
My wife and I work there on the Friday 2-6pm shift. If you can come before 4pm it's not much of a wait. After that we usually get a little bit busier.
Always full
Since I've been there it's pretty full but not terrible. They usually get people through pretty efficiently.
I would guess they stay fairly busy
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