Use new license for Decree Pro update?

Someone created a website for us using Decree Pro and we really like it. See https://missionchamber.org/ The person who created the website is not available, so we have no information about the license. 1. We would like to create a new user account, purchase a new license and update to the latest version of Decree Pro. What is the best way to do this and keep all our existing customizations and text? 2. When do you expect a new software version of Decree Pro? Thank you for your help