This story is a sequel to Ring Around The Moon -- Part II
Returning from hiding after Nightmare Moon's defeat, Cadance and Shining Armor have some wonderful news for Twilight. Then they encounter Tempest Shadow. And suddenly a simple question isn't quite so simple anymore...
Twilight, Tempest, and the rest of the Advanced Projects gang are back, trying to figure out their place in an Equestria which suddenly no longer needs saving... but which has no shortage of new challenges to throw at them, including some for which they may not be prepared...
For more of this AU, see: The Restless Princess
If you're new to the Advanced Projects timeline, this story begins Series 2, so you can start here if you'd like. All you need to know is, Nightmare Moon has been defeated, but has altered the timeline in such a way that Twilight never went to Ponyville, and has also wound up with a totally different group of ponies as close friends...
For a list of stories in the entire series, see Not Exactly Friends.
Read the review by Hopeling here.