By me as well as others I'm sorry to say :-[
If you have Skirmisher Cavalry in Cantabrian and they make a Skirmish move, the M2, M9 and M10 moves they are allowed in the Movement Phase will be reduced to a maximum of 1 BW instead of the normal 2 BW as they are starting/ending in Cantabrian.
Also applies if they make a Run Away response (and so come out of Cantabrian if they were in it) and choose to go into Cantabrian as part of the M2, M9 or M10 move.