Speaking of far cable reaches in that part of the country, WJAC and WTAJ got into that area of WV between Randolph County and the eastern panhandle. I also know that WJAC was (and might still be) on a translator in that area. Also, I remember seeing a listing for WTRF on cable in parts of Somerset County PA in a 1990s newspaper.
I think WBOY preferred competing against WIIC/WPXI (historically a very weak NBC affiliate) in the CATV days than against WTAE (one of ABC's strongest affiliates).
So far as I'm aware, WJAC is still on a translator in Moorefield WV (Hardy County), W29DH. In Moorefield, you would have these little compact UHF antennas on rooftops for the local translators, yagis, etc., it reminded me of antenna configurations in the UK where all TV broadcasting is UHF.
At one time, neighboring Hampshire County was even in the Johnstown-Altoona ADI. In the middle panhandle counties (Pendleton, Hardy, Grant, Hampshire, Tucker, Mineral), TV reception is, and always has been, "catch-as-catch-can" --- mountains on all sides, though with long, deep northeast-southwest valleys. Cumberland, Maryland, which has no TV stations (curiously, you'd think they would have had a network affiliate, and would possibly have been part of a "Johnstown-Altoona-Cumberland" market), serves as a default trade hub for that entire area.
WTAE also had the advantage of having their transmitter probably 15-20 miles south of the other Pittsburgh transmitters, thus being able to penetrate more deeply into West Virginia. That, plus having the ABC affiliation, rendered them the default ABC affiliate for all of northern WV.