I am quite new in IF. IF in 20.1 introduced center control frequency. Right now I am using a training server, where the change of ATC is quite chaotic, so the person in charge of the ATC zone can change a few times during the flight following in one particular zone. I had a situation when I have made “check-in” in the central control zone, got commands from ATC, and follow them. After 10 minutes ATC person in charge changed and I got a warning message. During long haul flights, it was previously possible to do other things (sleep, for example, go shopping, etc) meanwhile your plane is on autopilot with predefined flight plan. So of my friends have been flying during night time ( take off before going to bed, stand up a few hours before landing and land). And I think that it is possible right now to be ghosted and reported if you move somewhere from your pad during the flight.
How are you dealing with long haul flights with 20.1? For example, how to perform 17 h flights from Sydney to London? What about situation with long haul flights at the Expert server?