Sounds like a shift they call the Dupont schedule, also known as rotating 12's. After coming off your long break of 8 days, you work 4 nights, then work a 3 day weekend on days, then a short turnaround back to 3 nights, followed by 4 days during regular day shift (hell week). Then off to your long break! Then you start it all over again...
The way it's set up you get your regular 40 hours plus there's about 20 hours of OT built into the schedule. If you're gonna be on shift, this one ain't bad.