Wouldn't it also make sense to only stretch the skirt in the direction of the roll off point instead of symmetrically?
Roll off point is determined on where your rally point is, it can be either at the top or to the bottom of the naval factory. Hence it is symmetrical.
But it's still strange, as naval factories aren't symmetric, one side of the map will have an advantage in an up/down split map, because you'd have to place your factory much farther from the cliff on one side of the map, than on the other.
At the moment the horizontal distance has not been changed - what you see here (the green build skirt, not the circles - that is something else) is (horizontally) the same as it is right now.