Good question. I don’t know, and their site doesn’t say whether they carry forward negatives or not. I don’t recall why they were in the “no negative carryover” category in the first place; as BJF said, about half of the Playtechs carry over negatives, and half don’t. BJF supplied a list of Playtechs that don’t carry over negatives, and CPays wasn’t on that list.
For now I put them back in the “unknown” category. If you are personally experiencing negative carryover from a previous month (and if you are sure that this isn’t from a chargeback), then I will move them to the “programs that do carry over negative balances” category.