The score change can be caused by a number of reasons. It depends on the account type, which dates changed, etc. Overall, disputing bad accounts, even if reporting inaccurately, is a bad thing. There are safer steps to take via PFDs, GWs, etc. The dispute could have resulted in the CO updating date(s) which can appear newer. Sometimes, after a dispute clears, the OC will take it upon themselves to add lates where there were none before. Sometimes they will under-report a negative status and a dispute will cause them to start reporting accurately. If this was a CC CO, then there could be issues with utilization where a dispute will remove it when the account could actually be helping and that can cause a drop. Or maybe they increased the balance or decreased the reported CL and that can cause a drop after a dispute clears.
Wait for the dust to settle and all of the disputes to clear.
If any of these are unpaid, send a PFD.
If paid, mail a GW.
