ICAO callsign update

how often does flightaware update callsigns?

It’s not regularly updated, but we update them on-request.

how long does it take? is there an official channel i have to use?

I’d like to put in a request for a specific call sign change.

JAS apparently used to be: Japan Air System Co. Ltd. “Air System.” JET AVIATION FLIGHT SERVICES, INC (TETERBORO, NJ) is now using it with the call sign, “JET SETTER.”

Thank you very much!

Thanks, it will update in a few hours.