I believe the sealant in One Step is the same as Blackfire Paint Sealant, which only directs the user to wait until a haze forms to wipe off. I've also read that as far as actual cure times after buffing off, the wet diamond polymers are one of the faster cross-linking types, and under low humidity and decent temperature, 90-something percent can typically cure within an hour or two. This being the amount of time before one should layer or get it wet.
This makes me think that whether you wait to buff off or buff off as soon as it dries, either way the polymers should be bonded enough for the purposes of wiping off. If it is a more humid, hot day, you can always take caution and wait longer.