The days will be the longest they get at that time of year.
So, if you can get up early (I'm talking 4:30 AM), and hike until 9 PM when light is fading, you only have to do 1 1/2 miles an hour, or 2 with breaks.
So, yes, it can be done IF you have endurance.
You say you are a distance runner. Does that mean marathons? ultras?
Don't try to go too fast. You have lots of time IF you get up early.
20 mile days in that section is not so hard.
I'd do a few beforehand to show your body what it's getting into.