From the BOB website:
"We recommend that your child should be at least 8 weeks old before riding in a BOB stroller. Please note that babies incapable of holding their head up must have additional head and neck support to ride safely and comfortably. For jogging or off-road stroller use, children should be at least 8 months old."
So, at 10 weeks, he should be ok, I'd add a snuzzler or other infant support to be more comfy.
It's actually better for them to be out of the car seat too for a variety of reasons, either in a stroller that reclines flat, or at least as soon as possible in the stroller based on it's recline.