Big T companies like PM and RJR will move into, if not take over the space as cig profit goes down and mj profit goes up. The only thing keeping from jumping in the pool is the Fed. As soon as the Fed clears up the ambiguity of the law(s), deleting mj from the Schedule 1 list for example, and they will, big tobacco will jump in from the high dive. There's one commonality in all of this, CASH. All states will jump in faster then they adopted casinos, also. One more point, not only do the states make big tax profits, but save a ton on not having to enforce mj laws. Just as they did during the Volstead Act.
The way tabacoo companies will move in is via acquisition - not via establishing new start ups. If they go the route of acquisitions, they will pay a significant premium as the listed companies are already highly valued and they will need to make generous offers to close.
My prediction, if it does happen, hope you own that company's stock!