According to Google it's 311 miles from Boston to Charleston. I did the math and if he walks 5 hours a day (he'd probably walk longer, but let's account for foraging for food, fighting bandits, hiding from aliens, rugged terrain, getting lost, etc...) it would take him just over 2 months to walk all that way.
He better start hoofing it.
Nice way of hiding Moon Bloodstone's pregnancy by setting the "memory" in winter. Bulky winter clothes and having her only scene be sitting at a table was a nice idea.