I'm really not a fan of putting all of your eggs in one basket (i.e. running the same batch for all of your cells). I tend to mix my cells and replace every few months.
There's a new manufacturer of cells that came to market about 1.5 years ago. Approximately 9 months ago, they were having some major manufacturing problems and cells would start dropping out. Because of the shortage of O2 cells due to the pandemic, many people wound up buying these new on-market cells, including myself and a few friends. We noticed cells would drop out periodically throughout a dive, I only had one of these cells but it seemed quite flakey and a friend of mine with a (new to him) JJ was having very regular problems with his cells.
There was some heated debate about whether it was his cells or his JJ head, with one person even going so far as to recommend he through his JJ in the garbage. So without knowing about the manufacturing problem, and while trying to help my friend debug the situation, I took his 3 cells and put them in my JJ. During a dive I had a good cell voted out by two bad cells. A DIL flush confirmed that the good cell was voted out and that the bad cells were reading LOW. A bailout, proper exit, and disposal of the cells into the round receptacle were the solution. We replaced the cells in his JJ with another brand, and it's been flawless since.
There's a new manufacturer of cells that came to market about 1.5 years ago. Approximately 9 months ago, they were having some major manufacturing problems and cells would start dropping out. Because of the shortage of O2 cells due to the pandemic, many people wound up buying these new on-market cells, including myself and a few friends. We noticed cells would drop out periodically throughout a dive, I only had one of these cells but it seemed quite flakey and a friend of mine with a (new to him) JJ was having very regular problems with his cells.
There was some heated debate about whether it was his cells or his JJ head, with one person even going so far as to recommend he through his JJ in the garbage. So without knowing about the manufacturing problem, and while trying to help my friend debug the situation, I took his 3 cells and put them in my JJ. During a dive I had a good cell voted out by two bad cells. A DIL flush confirmed that the good cell was voted out and that the bad cells were reading LOW. A bailout, proper exit, and disposal of the cells into the round receptacle were the solution. We replaced the cells in his JJ with another brand, and it's been flawless since.