Mondays are for Masters, Women, and Juniors. Wednesdays there are races for 1/2/3, cat 4, and cat 5/one-day licenses.
women, masters, and juniors can also race on wednesdays in their categories.
i encourage you to ride out - it's more fun. there are some decent routes, depending on where you're coming from, of course. and the 7 train is fairly close if you're too exhausted to ride back.
when i'm tired after a handful of races, it's kind of a groan to get back on the bike with thirteen or miles left to go... but it's not so bad once you get in to it.