I write to the json import endpoint a list of contacts in "import_data" and one list id in "list_ids". Let's say one of those contacts is already in Constant Contact. That contact is a part of the "Second List" list. In my json import, I'm re-importing that contact with only one list in the "list_ids": "First List".
If I were to run the import, would the contact's membership to "Second List" be removed?