I would do it immediately, as much as you can, with no waiting for it to "cure." Some of the oils and solvents in carnaubas will begin to evaporate in those 2 days.
It is kind of whatever you want to do. No one can give you a specific number with carnauba waxes.
With synthetics you need to wait the time for the chemical reaction to take place. If you don't, then it'll affect the shine and durability of the wax. Carnauba you don't have to worry about that.
I have always heard you should wait atleast 4 hours between coats of carnauba. Just because I don't get time to wax everyday I usually end up waiting a week between coats