Thanks Ceph! Planes are color coded, as you probably noticed, but also in the top-left corner of the UI there is a number of arrows that indicate how fast the plane goes :)
And for our differently-sighted friends, who might struggle to differentiate color, each random flight code starts with a prefix unique to its color - BL for blue, RD for red, and YW for yellow!
Thanks so much for playing my game! I should have had a more intuitive guide to the user interface, it’s tripped a few people up.
And lastly, no, there isn’t a way to edit the flight paths once set. That’s part of the puzzle :)