I have a 21 year-old wood deck, which has been stained red at least 6 times. I want to use a new stain product called "Restore Liquid Armor Resurfacer" (made by Synta Inc.), which has a grit particle finish to fill in cracks and nicks. I scraped off all of the prior coats of red stain, but found some boards with severe surface problems. I had to replace 30% with new pressure treated lumber. Right now, my deck is a combination of old PTL scraped down to bare wood and new PTL. Is there a way to pre-treat the new PTL (sanding, pressure washing, etc.) such that I can apply this new stain product without having to wait 6 months for the new PTL to dry out to allow the new stain to adhere? If not, should I apply a coat of wood waterproofing to the scraped old wood in the meantime and simply wait until next spring? I live in Pittsburgh, which has a high humidity level in the late summer. Any advice is appreciated. Thanks.