do you have a pic you can post?

At work right now so will try to get picture up later. The grafts themselves look great its just that I had to graft high to get the size of the scionwood to match well with the size of the rootstock. All grafts are growing vigorously and show at least 8 to 12 inches growth each. I am hoping that it would be okay to bury the B9 rootstock deeper than in current pots once I plant them out in the fall but will this choke the tree or will new roots form on the buried trunk of the B9 rootstock?

On stock that young you shouldn't have any trouble getting it to throw roots when buried deep. I have buried several trees well below initial soil line to intentionally get the scion to root as well....a few of those on B-9.

It might slow it down a little for a year or two as it redevelops a shallower root system.

But if you don't want scion rooting why bother with dropping the graft height? Do you need branches that low for some reason?
Most grafts blend out nicely with a few years growth if aesthetics are driving your choice