Charge off vs In bankruptcy reporting

I recently was discharged from a Ch 13. My credit scores moved up over the 3 year period I was in the Ch 13 nicely, but the day that my discharge updated at the bureaus the scores fell some 70 points to where they were right after the initial filing. Bummer. My question is this, in the last few weeks I have submitted a few disputes to correct some items being misreported, 3 to be exact. The resolution brought my equifax scores back up to 635. however 1 of the three items a day later suddenly GMAC changed the way they reported a vehicle loan that was surrendered in the bankruptcy. Previously to the dispute it was listed on the credit report as included in ch 13 WEP plan like the other items, now it shows charge-off with a balance and an amount past due, both the same amount. M score dropped back from 635 to 607 in less than one day.

Is this right, legal?

Interest rates have gone up 4 times in the midst of me trying to fix all this stuff to prepare for a refi and it appears ill be waiting another 2 weeks at least just to see what magic rabbit they pull out of their reporting hat this time?

Sincerely
Demoralized