Ah yes, the Almost Christmas Long run.
10 mile people: 7 miles. 15 mile people: 9 miles. This is kinda short, and I'm hoping you'll find the time to squeeze those runs in. For added effect, try slipping in 20 minutes at tempo right in the middle. If you don't feel like 20, how 'bout 3x 7 minute cruise separated by 30 seconds? Make it fun. Or relax and just run long.