Is your current finish 1000  + polish, the stock surface?

It depends on how long you have let it go since you first used it, and it depend son how much more length you need/want.

If you have been maintaining the surface, then just a sanding to 2000 or 3000 and then re-apply a dose of polish.

If you have not been maintaining it, then you need to reset the base underlying grit level - you should do 500, 1000, 2000 or 3000 grit and then apply polish.