In Maastricht the nightshift starts at 2300lt and finishes at 0630lt. How it is divided depends a bit on the season.
At the moment all 4 of us come in at 2300 as we are still on 2 sectors. When we collapse into one sector, 2 controllers go to bed and get up again by 3am to sent the other 2 to bed. Depending on sector needs they sleep untill whatever time they wake up. But during summer they are most of the time needed again by 6am to open a second sector.