I'm so happy to find this site!
I recently added 6 English White quail to my collection of Coturnix, and have had nothing but trouble. Of course, this was my first time adding newcomers, and just put them all together. I noticed that they were all still separated two days after the introduction, so I spent some time watching them, though I didn't notice any harmful behaviour. But this morning (3rd after intro) I went to check on them and 4 of the 6 had been beaten up- blood around the beak and ruffled feathers. In the 10 minutes I watched them, my Browns would chase around the Whites. So Now the EWs are in their own pen. I thought maybe if I reversed the introduction, it would work better, so I put one of the browns in with EWs, and within a few minutes, the Brown was being chased. I guess they'll just have to remain separated.
But back to my happiness of finding BYC, I have now read that the proper way to introduce new quail in is to put them within sight of the original group, but separated so that no fighting can occur. We'll see how that works. Or if it's just the EWs being bullies.