When you land
Turn the Departing line on after you arrive. That is when the plan starts.
Turn the travel line on
Choose the travel line for mobile data and turn data roaming on for that line. Keep your usual line on for calls and messages.
When it starts
The plan starts when the eSim first connects to a network in a country it covers. Installing it early does not use any days.
If there is no data
Turn on data roaming for the travel line, choose it for mobile data, then restart the phone if it still does not connect.
No data after you land