Hope you are well.
Very sorry about the delayed reply. You should be able to renumber the line and then port your existing number to a Cloud platform, however I would speak to our Customer Options Team before you would initiate any porting. You can get through to them by calling 0800 800 152, they are not available on chat unfortunately, but they would be the best people to advise you when it comes to making any changes to your existing services or packages.
They are open Monday-Friday 8am-6pm. 🙂