Smoke rounds that are being re-positioned by an enemy player (as per BA rules as written) cannot be re-positioned off the gaming surface.
Smoke rounds being re-positioned by an enemy player or by “wind” move around buildings, not through or over them. The movement is in the nearest possible direction as determined by “wind”, or any direction as chosen by a player. Player chosen direction is to a maximum of 6″ as per rules as written (i.e. no hopping of buildings).
All other rules as written for smoke rounds apply.