I do not know if carnuaba requires time to cure - my guess is no.
But, I think
Souveran accomplishes much of it's success through the 'additives', as much as the carnuaba. Those 'delivery vehicles' (petroleum based?) make it happen, as most of us agree.
The insert with the product clearly says: "Procedure For Layering Wax:
After polishing, wipe on and buff the first layer of Souveran. Allow this layer to cure for 12 to 48 hours. Follow with a second coating. Notr: The first coat must have time to cure. APPLYING A SECOND COAT IMMEDIATELY WILL NOT PRODUCE THE SAME RESULTS."
So, they've tested the product more than I have. I'll let time tell the story.
BTW, that P21S is pretty cool. It is on the 'other' half of my tester.
Jim