Yellow leaves are normal near harvest and it’s a good sign that you can harvest soon, even though there are plenty of other ways to note when to harvest. I’d keep a normal nutrient feed this week and next week flush, then water with just RO water or distilled or whatever you’re using for the next couple weeks. You still have to balance that PH during your just water feedings so don’t skip that step but yeah man, I don’t see any problem.