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Which means waiting a few weeks, not days, if you are doing it as a new build. But an old finish will be fine. Sand it over with say P240 so that it can key into the surface (or it may not adhere that well), and I’d then give it a good wipe over with naptha (lighter fluid) and a clean cloth, just to remove any possible contaminants from the surface.
TTBOMK the general and (accepted) rule is:
lacquer over poly = OK
poly over lacquer = NOT OK
The reason being that lacquer (even acrylic) gases of for months (years?) and if covered in poly, those gases can't pass through and will lift the poly. As with any questions about finish compatibility, test on a scrap piece before your guitar.