I work in a professional cabinetmakers shop. Finishes don't take that long to cure. And it should not take more than three top coats to produce a strong professional finish. Read the label on your product. Nitro cell lacquer dries to touch in ten minutes, dries to handle in twenty minutes and is able to be recoated in thirty to forty minutes. Then its 24 hours to Harden. So I can put three coats on furniture, using the manufacturer instructions and be done in a day. Automotive may be different but it won't be that different.
Can't argue with the manufacturers instructions.