You're in good company! So many projects, so little time!
I'm the same way! Glad you will be joining our January KH-KAL for the seamless blanket! Just work on it as you can. The scarf and hat for your relative won't take too much time away from the blanket project. Some of us know that we will be working on our blanket for months, maybe even more. That's ok, too. A stashgan can be an ongoing project for an entire year. As stash or leftover yarn becomes available, just add another log to the blanket!