Hello - :seeya: I am brand new to posting, and even to Websleuths, but have been following this case as it is somewhat local, and I go through that area all the time going between Oneonta and Cortland. As others have mentioned cell service is spotty in that area, my sister used to have an ATT iPhone and would get service more frequently along that route than with I did with my Verizon iPhone, but depending on the model iPhone and how frequently roaming capabilities are updated (you are supposed to dial *228 every so often to update the phone) it is possible to have some service in that area. Also, not sure if this plays a role but there are also areas where you can receive texts but no calls - maybe the find the iPhone app works on the same principles as texts.
Another thing I thought I would mention is that I hate going through Norwich on 23, especially since they installed all the stop signs at the one end before you turn. I bypass Norwich by turning where the Mobil and Valero stations are (sorry not sure of route names), then going to the stop sign and turning left, (this goes by an NBT Bank that is fairly close to the road), turning right at the light and then turning left and going by the Country Club. This brings you back out on 23 fairly close to where the cell phone was found, and could be a possible path of travel. It also eliminates any backtracking. Also, when going to Cortland I take another shortcut when I get to Cincinnatus, and cut over I believe Telephone Road. There is a lot of open farmland and woods along this entire route.
Sorry this is such a long post, and forgive me if I have mentioned something that has already been mentioned. I hope that they find Jennifer soon.