First question is what size brisket? A 9lb brisket will be different than a 15lb brisket.
Second is do you plan to wrap it? If you smoke at 300-325 for 5-6 hours until the temp reaches 160, then wrap tightly in butcher paper or foil, it will only take another 1-2 hours to finish.
However then you need to let it rest in a cooler for at least an hour.
I'm thinking 10 hours is right at the outside edge and leaves no time for error. Better plan for some appetizers at 4 and give yourself some extra time...plan to eat at 5 or 6.