I have painted a guitar with Behr Marquee Semi-gloss enamel (Water based).

According to their website:

• Dry time : 1 Hr
• Re-coat time : 2 Hr
• Cure : 30 Days

I want to shine it with Bulls eye shellac.

My questions are:

• Do I need to wait 30 days before applying shellac or can I do it after 2Hrs, or 24 Hrs?

• I need to sand brush lines from the painted surface. How soon can I start the final sanding before applying shellac?