Does your 646 include the reported 5%? Or was util higher w/ the 646 score?
For max points, get all CCs to report $0 except for one and get one to report a balance of under 9% of the CL. Certainly everyone's credit is different. That sweet spot may be 4% for you, 1%, 8%, whatever. Trial and error.
If the increse was done with out a hard pull I doubt you will see much change if any in the score.