edit: In this archived thread: https://devforums.apple.com/messages/1069874#1069874 it looks like @amandavoss was able to fix the issue for a few developers. I'm still unable to get Game Center to work in the released version, but it still works as expected in the sandbox with my development build.
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It looks like my Game Center Leaderboard Sets are not showing in my game in the App Store released version. When I switch into Game Center sandbox mode, I am able to see the leaderboard set( i.e. everything works as I expect ). My game just got released a few hours ago, so I don't know if this is just an issue of 'wait and it will fix itself' or if I should be worried that I need to change some settings in iTunes Connect. Anyone else have some experience to share?
Thanks,
Mark