So you have your wishlist sale. I guess that's nice, I've no way of knowing which items owe their discount to that sale. I'm putting some stuff in a cart. I take something out of the cart and the sale price is gone. Happened twice! Oh, joy. Well, I was figuring stuff out. Since that's the way your software behaves, you basically hosed a vendor out of some sales today. Good job! Multiply that by however many customers had the same thing happen. Not that thrilled right now. 

IMO, the solution would be to make it so that items in the wishlist stay in the wishlist until they're removed (delete) or actually purchased so that an item could be on the wishlist and in the cart at the same time.

Every item that was on your wishlist prior to the sale starting (unless the vendor opts out of the wishlist sale) was part of the wishlist sale. Those items are all marked to 50% off  

This was explained the last time we had a wishlist sale and once it’s pulled out and put back in the wishlist the date changes to a date newer than when the sale started and therefore makes the product ineligible for the wishlist sale discount. 

Tima C

That’s a problem with your store, then. It would be good if you could fix it instead of trying to explain that it’s somehow my fault the discounts vanished.