That's how I ended up this last time, but I messed around for much too long trying different things. Their coop is only about 16 sq ft, but last time I was separating them completely (new duck with a friendly old duck, and two ornery ones together). One couple in the coop at night and the other couple in a dog crate outside the coop. They did assimilate to each other much faster when I installed a separating wall of expanded metal in the coop and housed a couple on each side. This way they could see each other but not harm anyone. I guess that was my first real mistake of duck ownership, second one being overly confident in their pen. Live and learn.
I hope this new duck transition goes as smooth as you say it should
I was told to wait until March or April, does that sound right, Miss Lydia?