I think you can turn it off in your Avast web account for that particular device -- I know I did it, just don't recall where exactly.
However, I am still bothered by the texts my phone send to my girlfriend's number every time I am abroad and many times.. I don't understand why can'°t I turn it off? If I need the location data, I will log into my account and ask for the phone to report it. I don't need texts sent each time I travel (and I do that a lot!).