It depends on how the business has configured this. By default, filling in the address form on My Subscription and submitting it sends your new address details to the business by email as a request — nothing changes immediately, staff review it and apply the change, and the request is logged on the subscription's history. If the business has instead turned on self-service address changes, that same form updates your subscription's shipping address (or pickup point) right away when you submit it, with no approval step.