The last 3ft (mast work)
Shouldn't be a problem. But you do have to stand up in the foot straps and kind of get up out of the seat to get over the mast head. The last few feet can be tough because the ascenders on the ATN rig tend to be right up against the mast at that point, and hard to manipulate. You really need to use the rigging to take your weight off the harness to move up high enough to get over the masthead.