Flipped/Limbered 81mm Mortars and Col Shifts

[Poor Yorek]

If an 81mm mortar platoon is flipped to its limbered side and comes under BF or DF, do (or should) the col shifts still apply? The Combat Tables make no distinction; so, by the letter of the law, the answer presumably is "yes," col shifts do apply. Just curious if anyone else has pondered this question?

PS (perhaps a better way to have phrased this is to question whether such a unit ought to be granted an exception to the col shift)

I should add that I'm thinking specifically of 81mm where the limbered side can move on its own by foot (essentially moving not unlike an HMG platoon) and not, for example, a 120mm whose limbered side must be towed (where I'd have no question regarding the col shift vs. the limbered side as the unit is still particularly vulnerable).