E6 use the callsign GOTO FMS as the FlightID.
You can use this link to find the first active E6 flying.
You can also use the 'Filter' option on Planefinder to only show the E6's flying on the map.
Some unknown reason the E-6B listed under this airline name " Walter | Linkoping ".
Set the Planefinder App to send alerts for the E6 aircraft using the call sign " GOTO FMS ".
GOTO FMS means GOTO F