Your motor would be destroyed in an hour. Don't run more than brief bursts to avoid overheating.
It doesn't make sense that your voltage would rise overnight. 12.65V is full charge on JCI batteries. When you first unplug the charger you'll see a surface charge, which will be about the output voltage of the charger, for several hours, but it will decrease to 12.65V over that time.
In your first post, you mentioned the Optima which made me think the TM batteries were Optimas, which have a 13.1V full charge voltage.
Have you checked the electrolyte level in your TM batteries?