If you turn from route 100 onto the Arlington-Stratton Road you will come to the bridge which is being rebuilt and will not be able to cross. This isn't a huge problem because taking Newell Hill Road to W. Jamaica Road will get you back to the road (this turn off is just a little north of Arlington-Stratton Road).
Part of the confusion is the variability in what the road is called. There is one long road coming from Rt. 100 in West Wardsboro which crosses the LT/AT and makes it almost to Route 7. The road has 3 different names: Arlington-Stratton Rd, Kelley Stand Road, and Stratton-Arlington Road. It seems like the name change comes at different places on different maps.