If it checks with Apple servers every time you execute a new binary, what happens if you don't have an Internet connection? Are you just unable to run new code?
replies(4):
It waits 5 seconds while trying to connect, and then it gives up and caches the program as un-notarized, allowing it to run faster on later executions.
Notice that notarization seems to be disabled if the network is disabled from within the OS. To observe the 5 second delay you need to cut the connection outside (e.g., on your router), while the mac still thinks it is connected. I observed it by running catalina inside a virtualbox, and disabling its network.