long runs marathon coach plan

i'm in the fourth week of my 12 week coach plan for a marathon in april. The longest run is 10 km (1:07 hours). Isn't this very low milage? Shouldn't I run 16 km in this stage of training?

I also find het very hard not to see the workouts planned for the weeks ahead. I only see them 1 week upfront. So i don't know how the milage is for the upcoming weeks.