With the upcoming release of the wonderful A220-300 to Infinite Flight it led me to search FR24 for some routes to do with this aircraft. When looking at a few AirBaltic routes like the Stockholm flight for example it has the callsign in a unique format to what you would usually see with a letter in between two numbers (Air Baltic 1M2) which is different to what you would usualy see in Europe for example (Ryanair 6BN) where they would have one or two numbers followed by letters.
When I tried to test the Air Baltic callsign in app it came up as an 'invalid callsign" where it could only contain numbers and two suffix letters. My question is and i do appreciate that it is rare enough as far as i know, is there a particular reason why there is a certain format for the callsigns? And if perhaps this could be tweaked to accomodate real world callsigns like these? As a realism freak it would be hard for me to use unrealistic callsigns or having to resort to the flight number as it is different from ATC callsigns.
This is just out of curiousity more than anything. Regulars, if this is in the wrong category please do not hesitate to move it to the correct one.