I had one item in my basket that went down, as I was watching it periodically, but right before 3 pm, it went back up. LOL! It was still a good deal, much cheaper than it was months ago.
I noticed that, too - an item had gone down and then back up.
I have benefited lately from some of those ‘per cent off coupon at checkout’ deals; more in fact than I’ve ever done with Prime Day.