Thanks for you reply chief, however, I have conflicting evidence. I'm quite dubious of lvcs on speedos, so I also run a cell monitor with a hideous bleeper on (they simply plug in the balance lead) they go off when the cells reach minimum voltage, and they show what each cell is doing voltage wise too.
I was using one these, each cell was holding 0.02v tolerance and when the incident occured, voltage was at 4.15v +- per cell.
So definitely not flat