DEALING WITH POLYMERIC SAND
High pressure washers and surface cleaners tend to blow out poly sand in an inconsistent pattern, making it difficult to repair the poly sand prior to sealing. In addition, your sand will not completely match the color of the previous sand, making the issue more noticable.
If you're planning on removing polymeric sand, with the pressure ,wand plan on removing 1" of sand in all the joints, or at least as much as possible to allow consistiency with the new sand.
You may opt to not disturb the polymeric sand, and soft clean (softwash), rinse thoroughly, and apply the sealer since joints are already stabilized.