Don't get hung up about the novice thing. However crap you think you are, there'll be someone ten times slower out there. And don't worry about the knee-down thing either. It'll come. Or it won't. Either way, it doesn't matter. I've been riding on the road for 16 years and only got my knee down for the first time last October. Been making up for lost time since though
Current conditions notwithstanding, you might be pushing your luck a bit at the end of September. Unless you like rain, anyway.