Too many cards with balances

On EQ5, when I have more than 2 cards with balances, I get reason code 23, "You have too many credit cards and/or open-ended accounts carrying balances." I might lose as much as 7 points for when I go from 2 to 3 cards with balances. I'm unsure of the exact number of points lost because of conflation with Accounts With Balances, but I know there's a threshold at 3 cards because I have seen the reason in third position there, and it vanishes when I go down to 2. I think I see hints that 3 is treated the same as 4, but there's another threshold and bucket at 5 & 6.