@suzubelle @animeknight
Take a look at the chapter list for the series and you can see what's going on.
Mangasushi started translating this series, then abandoned it for 4 months, so this group picked it up (series are generally considered dropped if there has been no work on it for 3 months). Another 2 months later, after this group had already released 4 chapters, mangasushi, for whatever reason, decided to pick this back up again. Since then, they've both been releasing chapters.
This groups translation, cleaning, and typesetting are all superior to the mangasushi version, though I'd agree that the difference isn't so dramatic to justify having two versions. Also, I don't know the whole story and this is just my opinion, but I think it's BS for a group to restart work on a series that they hadn't touched for 6 months, after another group started actively working on it.