Why not change the version number with the same package name and when published will replace the old one and existing users who updates the app will start to get charged. Remember to indicate clearly on the Play store's description why users will be charged and the new features introduced to the app.
On a separate note, Am struggling with Google places Autocomplete in CN1...I tried to follow your post on this forum but it was hard for me to understand. Kindly assist me please.
Thanks