I have a perfectly barbecued 10-lb. brisket in the freezer and just found out that I should heat it tomorrow to take to a neighbor who has had a death in the family. I thought I might just take out the frozen brisket when I go home for lunch tomorrow, put it in a 200 degree oven just before I go back to work at 1:00, and pull it out when I come home at 5:00. Do you think that's too long? Our friend who smoked it suggested "low oven about three hours" when he gave it to us. Someone on the internet said "225 for two hours." Please help, I don't want to ruin this beautiful brisket, much less take a dried-out brisket to my neighbors. Thank you.