"Either / Or" option for flight alerts

I’d like to request that when setting up indefinite flight alerts for a certain aircraft type at a certain airport, users could select their specified airport for “either” arriving aircraft “or” departing aircraft.

Example: Right now, if I want to track all MD-11 aircraft arriving or departing at KIAH, I must set up two flight alerts to do it. One for inbound, and one for outbound flights. I’m looking for one alert that allows me to set up all activity for [AIRCRAFT TYPE] at [AIRPORT LOCATION].