A warning message to act as a prompt to check when setting altitudes > 3,000 that do not conform to the semi-circular rule. Sky Demon is a VFR app so that removes uncertainty around it being a VFR sector and makes the rules easy to apply. For instance, should I plan to fly 4,200 feet on a magnetic track of 200 deg, perhaps a warning message could appear at some stage in the workflow (on Save perhaps) ‘Semi-circular rule requires 4,500 feet for this track.’

Eurostar EV-97

Waste of time. Too many pilots don't need to fly semi-circular rules and if you do and don't know what level to fly, hang up your headset.