when to apply hotcoat?

After applying the laminating the board, do I have to apply the hotcoat right away? Would it be possible for me to laminate my board first and then hotcoat it the next day?

YOu shoud wait long enough to sand the lap. The next day is fine, alot of boards sit for days in the lineup waiting to be hotcoated.

The standard procedure is to lam the bottom, flip, clean up
any bumps, lam the deck. Then clean up the lap & hot coat
bottom. Pull the tape & hotcoat the deck. Let the board totally
cure before sanding usually next day or later.
That being said, many lams wait a day or two before hot coats.
It is important that they be kept in an environment with little air
movement so dust & particles are not allowed to settle on the
sticky lam. If you can keep the dust down and not look & mess
with the lam too much, wait a day or so if you need to!