Error in certain data tags of arrivals and departures

In live flight tracking, the data tags for arriving and departing aircraft sometimes display ESTIMATED in lieu of the altitude and speed info. Also, the aircraft icon always tracks directly to/from the the airport, instead of following usual arrival and departure routes. This situation happens frequently at Anchorage (PANC/ANC), but I have seen it at other locations on occasion. Anyone know the cause, or a remedy? :confused:

foxy1