Hi
My son's A1C initially went up when he switched from MDI to pumping, but I believe that's because he had significantly fewer hypos on the pump, than on MDI
I've gradually become more pro-active - using the advanced features of the pump to increase or decrease temp basals, using extended boluses to cope with foods which digest slowly etc, setting different basal profiles for school days and weekends - and gradually his A1C has come back down again and his last one was the best ever. It has taken me two years to tighten up his control using the pump, but he benefitted from the freedom it gave him straight away.