There are some precedents for bringing PBS programming to unserved markets that haven't been considered here.
In southwestern Virginia, after Blue Ridge PBS sold the spectrum it was using for OTA service in Norton (WSBN) and Marion (WMSY), it started a "PBS Appalachia Virginia" service that's considered a separate station even though it's available only on cable and streaming.
Just to put a little more color on the situation, the Tri-Cities TN/VA market was always in a strange situation regarding PBS. They started out in 1967 with WSJK in Sneedville, broadcasting on channel 2, an allocation that had to be squeezed into the tightest possible space, to protect WSB, WDCN, WFMY, and possibly WLWD (not sure about the latter one). Sneedville and only Sneedville would fulfill this criterion. (One early proposal was for the public TV station on channel 2 to serve both Tennessee and neighboring Kentucky.)
The idea was that WSJK would serve both the Tri-Cities and Knoxville markets, but even with the lowest possible VHF channel (good propagation characteristics), this was a challenge in that kind of terrain. The station would be served from studios in both Knoxville and Johnson City (Hancock County is actually in the Knoxville market, not sure to what extent markets, then called ADIs, were delineated back in those days, nor where Hancock County would have fallen in 1967). In actual practice, reception in Knoxville was dodgy, so in 1990 a second station, WKOP, was created to serve Knoxville on channel 15, with the two stations simulcasting.
And then there was WSVN on channel 47 in Norton VA, a satellite of WBRA Roanoke (which has a massive signal of its own on OTA channel 3 from Poor Mountain, a catbird seat if there ever were one). WSVN (which later became WSBN when WCKT Miami wanted those call letters in 1983) went on the air in 1971, followed by WMSY in Marion in 1981. WSVN could be received even throughout a large portion of eastern Kentucky and was carried on cable as far north as Irvine. Much of the Tri-Cities market was able to receive one or both of these stations, but they were closed down in 2013 due to budget cuts (there is nothing new under the sun).
To this day, OTA PBS service in the Tri-Cities market isn't what it could be. PBS Appalachia Virginia really needs an OTA presence. I've even wondered if WLFG Grundy might be able to spare one of its subchannels, though as a religious nonprofit, any tax advantages (possible deduction due to PBS Appalachia Virginia being a public broadcaster, I'm just guessing) would be of far more use to WCYB.