I have a seperate Twitter share button outside of Game Center too. However, in Game Center's Twitter Share button there is a message that states ""Check out my score on High Scores playing Station X". Recently I found out that there is already an app in app store with name Station X. So I changed the name by adding an extra letter. I tried in iTunes Connect Game Center leaderboards changing the name but I can't see a place to change name of app in Leaderboards.
How do I change the name of app in Game Center when I click Twitter's Share button so the pre-populated message with "check out my score on High Scores playing Station X" now would become Station EX instead?
(I'd like to add my app is not in app store yet so I don't know if that makes a difference with changing name in Game Center prepopulated message for Twitter share button.)