TBH I have a somewhat similar situation myself, which is why I mentioned to you to call via phone. I have about 25% degradation, according to Tesla Energy Tier 1 support, and my powerwalls are about 1.5 years old. For about 24 hours it made me frustrated, then I thought to myself: There is no way that these things wont degrade another 5% in the next 8.5 years. So, I am not sure how you feel about it, OP, but what this means to me is that at some point they will drop below the value for warranty replacement, and they will have to be replaced.
OP, I use self powered mode, no idea what mode you use. I have not changed anything about my usage pattern at all. My reserve is set to 20% right now, and I go from 100% to about 25% daily, and am using virtually no energy from the electrical grid, same as I did last year.
Said another way, I am continuing to "use my powerwalls" with the expectation that, at some point in the next couple of years, they will lose another few percentage points of capacity, and will need to be warranty replaced. I have no qualms at all about "using the battery" because I am simply using it in the manner it was designed.
I came to the realization that I would much rather have this much degradation in the powerwalls now, than have them be at 26% in year 9 or something, where they would likely (with my luck) drop below the warranty value right after the 10 year installation anniversary.