Going back to the original OP issue, I have mentioned before that I was surprised this summer by my 6s not needing 15+v overcharges like before.
On a regime of 14.8 then 14.4 till dark, they did fine, reaching baseline SG enough times in the sunlight time available that they didn't need an equalize.
Mex has mentioned this effect too. It seems if you do shallow cycles as with solar, and get close to 100% often, the requirement to equalize changes so you can do it less frequently
This is not the same thing as leaving them on a 14.4 PD converter forever, where RJ says they will last ten years no sweat, but it does show that in certain circumstances, you can go without equalizing for a long time. Just be sure to use the hydrometer to confirm everything is going well. If not, then do something about it.
