Not always. My previous statement is still correct. AirlineFlightSchedules will generally (not always) be the gate arrival times, since that is what the airlines commonly publish in those advance schedules. However, they can publish any time they want and AirlineFlightSchedules would not be able to distinguish it any differently.
Similarly, FlightInfoEx will generally (but not always) be the runway time (wheels down). For example, in areas or time periods that we do not have complete data coverage that would allow us to receive air/ground indications we may still have a secondary airline data source that provides us with just gate arrival times. In such cases, FlightInfoEx will return an actualarrivaltime that is just the gate arrival time since it is the first arrival indication of any type that we have received.
Gate times were not available for any flights on our website at the time the FlightXML2 API was being finalized. Changing API definitions by adding new fields once it has been published is problematic for some programming languages that use static compile-time web service definitions, so we had to add a new method instead. Additionally, there is a slightly higher data licensing cost for us to provide gate times so do internal accounting differently based on the two functions. There will be changes in the upcoming FlightXML3 that should improve the usability of the function definitions, so look forward to that in the coming months.