I could be wrong, but the afternoon bus schedule below may be for the bus Abby would take home (after going to Redstone, it seems to head north along route 302/16). The stop closest to her home may be the one at Echo Acres at 3:07. I'm not sure where the "Mt. Washington Hotel" stop is (I can't find a hotel by that name in North Conway in google, so maybe it goes by a different business name or maybe I just didn't look well enough). Maybe that stop is the Mount Washington Valley Inn???:
http://www.sau9.org/SAU9/Busses/Routes/2013-14_Routes/Linda_K_13-14.pdf
Look again it stops at Valley View Rd. at 310pm. 40 minutes by bus or by walking.