I have entered only one power setting (Max Cruise) with several levels.
The airspeed type I chose is True (TAS).
Of course the airspeed depends on the level.
I then planned a flight with a cruise at a high level, and a step descent due to airspace.
On the plog each level leg is shown with the Seal Level TAS, and the time for each leg is calculated with that TAS.
Climbing and descending legs are shown with a climb speed or a descend speed, but level legs are shown with the SL TAS.
Have I forgotten a parameter somewhere? Or is it a bug?