People who have lost weight - when did you make the decision to go down a ring size?

TL;DR: title

I have an Oura ring 4 that I bought about a year and a half ago. Out of warranty and used my one free replacement for battery issues. I gained some weight a couple years ago due to medical issues but I’ve since lost 20 lbs in the last couple of months. I’m now within the weight range that had been my normal my entire adult life prior to said medical issues. Ideally would like to drop another 10 ish pounds but I’m in no rush.

My ring is now officially too loose. It moves around constantly, falls off when wet and I have serious gaps in my data. It’s been this way since mid July. The gap between my finger and my ring when I make a fist is about the size of the thickness of two Oura rings. Considering it is summer, I know it is probably only going to get worse in the coming months. I’m torn though - I don’t want to jump into a smaller size for fear of gaining the weight back, but I also feel like I’m wearing a useless $500 piece of technology.