Please note that after upgrading to iOS 14, you will be asked to permit AvTraffic to "Access devices on your local network".
This is referring to the connection AvTraffic requires to send traffic information to AvPlan or OzRunways. You need to allow this in order to continue to send traffic between apps.
You will get asked the same question when you first run OzRunways or AvPlan and you need to allow this for them too.
You can change this in Settings/Privacy/Local Network.