Originally Posted by Ldnn1

I tried this once and no dice. I’m not sure what the exact cut-off is and whether same-day is possible but I don’t think they allow it less than at least a few hours (if not more) beforehand.

Also even if the system does allow it in theory, space is capacity controlled so if there’s a queue they are presumably at capacity, so wouldn’t solve your problem anyway as there would be no spots to book.