Your flight, 1071, was cancelled but the aircraft flew from TPA to CAK as flight 9715.
Here is the info from FlightAware and
here is the flight tracking info.
Airlines often assign flight numbers in the 9000 range for charters and ferrying flights. I'd say AirTran has a lot of explaining to do as to why they left a plane load of passengers in TPA while they flew an empty plane to CAK and with the above info/links you have indisputable evidence.