As far what you heard? You heard it a bit inaccurately. The LBC had a programming error which resulted in its reporting false degradation to the BMS. The error was corrected in the SW upgrade. Getting the SW upgrade is HIGHLY recommended simply because the BMS will only use the part of battery the LBC reports as good. Now this only applies to 30 kwh packs.
The OP described the situation accurately. Your version I consider to be less accurate, because it implies both that there is no other problem with the 30kwh packs and that the BMS update always solves the problem of accelerated capacity loss when it is applied. By now it's become clear that neither of those assumptions are true. Some 30kwh packs had just the inaccurate BMS programming, while a significant number of others have suffered real, rapid degradation even
after the BMS update was applied. The 30kwh packs have TWO issues, not one, and the BMS update only solves one of them. I continue to give the same advice to those looking for a good 30kwh Leaf: if the car
has never had the BMS update but still has 12 or 11 bars, the pack is one of the good ones. If it has had the BMS update at least six months ago, and still has 12 or 11 bars, it is a good pack. Those cars that had the BMS update recently can only be verified good by a range test or a charge capacity test, unless they have already lost two or more bars since the update. In that case they have bad packs.