Those are both trichlor. Both will push your pH downward and continue to raise your CYA. If the tabs haven't been opened, I would go ahead and return those. Otherwise, if you can store them in a cool dry place, they'll keep until next year. I wouldn't use any more of the 4-in-1, either...switch to bleach. It's cheaper, better for your pool at this point, and won't keep raising your CYA.