Also found out today that you can't delete any data from your delta live tables or else the process fails with an error:
......
This is currently not supported. If you'd like to ignore deletes, set the option 'ignoreDeletes' to 'true'.
It's not possible to set the ignoreDeletes to true either.
So, unless you're happy to keep the data in your Delta Live Tables forever, you've got a little problem. We're looking at workarounds but nothing pretty yet.