Preseason is over, season starts Wednesday, and they're all ESPN regional games. So i think nhl center ice coverage actually will start on Thursday. They're very late with their schedule, rest assured that it'll be here. Directv has one up on their site, not sure how reliable it is since it lists every single game and most games are TBA.
Center Ice channels have been moving around quite a bit the last few days. Several were moved this morning. None were turned on as of 7 AM EDT this morning. looks like they are attempting to obtain the best usage of bandwidth.
As of the last update I got from an anonymous contributor, all but channel 540 are now at 119°.
As John said, all the channels have been moving around quite a bit. So this could change.