According to Historical Topo Maps (historical.mytopo.com) from 1953 and 1934 there was a Wye at Squa Pan Jct. (Ashland, ME Quadrangle, Southeast). The 1953 version shows more tracks south of Route 11 than the 1934 version does. These maps are a great resource for research of any kind. Also a quick check using Google Earth shows the Wye quite clearly. It appears to be currently usable.
Mark