There has been talk of a couple plants that may come back at some point but very few and Dayton was never in the cards.
The Lordstown deal has rumored for several years that the Buick would go in there with the Verano at some point but it has not happened.
The last time I was there the Cruze line was on a new line in the plant and the old Cobalt line space was available but as of this point nothing is happening.
GM could bring in a totally different product with this space on a second line and build a different platform vs. the new Cruze platform. The UAW there has learned their lesson and found if they cooperate they can be rewarded well with more work. So far they are doing so. At times in the past this was not true.
This is still the largest plant GM has in the US under roof. They have a lot of space they could add too if needed but still no word.