By all means, just import the mobile numbers of your existing subscribers.

1. Login into FrontPage from the web.
2. Go to Manage > Your Service > Subscribers and click the “+ Subscriber” button.
3. You will be given an option to add phone numbers of your existing subscribers.
4. Once you have added them here, you can intimate them to join FrontPage.
5. When they join, they will start seeing your paid service automatically