Hello, Had happened a few times now (almost always i would say). When i start a new turn, my battlemaster bonus is not showing (nor being taken in account) in friendly units stats UNTIL I MOVE the battlemaster unit, it shows and works fine after i have "activated" the battlemaster unit. Has happened with a full FS bgs, firk mastermind and a darkmarsh instigator so far, in skirmish games. I'm too lazy to look for computer specs srry u.u
Had any form of cleansing near? I've had the same wtih a KF BG where Cleasing Emerald seemed to remove it, because when the champions were out of range the buff stayed. It would otherwise fade until the Battlemaster unit moved as you have described. Cheers~