At 250 grate, probably around 6 hours at most.
At 225 grate, probably 6-8 hours.
At 210 grate, probably 8-9 hours.
I cook them higher than that, usually around 280 lid, which would be about 260-265 grate. Runs about 5 hours, but it does kind of depend on how thick.
I"ll foil in a tray when I want it to finish....might be 2 hours, or might be one hour. I'll add onions, wine or stock, and cover. Depends on the cut.