@helplesshopeless how are you getting on? We do 2/2/3 here. It's not the same as 2/2/5 as someone suggested above. It's Mon, Tue stay at parent 1, Parent 1 drops at school, parent 2 collects. Wed, Thu stay at parent 2, Fri, Sat, Sun stay at parent 1, Then Mon, Tue parent 2, Wed, Thu parent 1 etc. Been doing it for over 2 years now.
It sounds complex but once you get into it - it is ok. We use a family calendar on our phones to manage it. We also drew up a parenting plan - Google that and you'll get a template to follow. I found that very helpful for communicating and I wish we'd done something like this when our child was born and we were together!
It took me a long time to get used to this way of living. You just expect to see your child every day. My daughter was 9 when it started. She got her mind round the routine very quickly, knew where she was going to be etc.
I must say I find the weekends when I don't have her a struggle but the 2 free weekday nights are pleasant and a rest after working all day.
The disadvantage of this routine is that the week nights are not consistent so you can't do a regular class/group. But i didn't want to have 5 nights of not seeing her, so it seemed like the best option at the time. You need to be very organised and have the same clothes, toys etc at both homes. Our homes are now 10 min walking distance - that really helps. I would say in these circumstances it was an ok option and you do see your child very regularly. You will see her more frequently than you do just now.
But it sounds like you've managed to cope with 6 nights apart already, so why does he want to change it now? Why is this extra night necessary in his opinion? Is it to do with child support or is it just about control? Would the best compromise be week about like others have suggested. If you can handle 6 nights, could you do 7?
I don't think my daughter would have coped well with being away from me for much more than 3 nights. I wouldn't say she has enjoyed this way of living. The split came out of the blue and has been a struggle. She hates living split between the 2 homes.
I am interested in what @TipToeStep said about Camhs and the main home. Can you elaborate on that? My daughter (now 11) is now saying that she doesn't want to follow this routine and mainly wants to stay with me. Circumstances have moved on and dad has a g/f and she doesn't want to hang around with them playing happy families. It's become very stressful and traumatic and she can't settle at her dad's. So we are in the process of changing it. I suppose this is the nature of co-parenting and you need to adapt. The Parenting Plan helps with this aspect as you are supposed to regularly review it.
I feel for you. It's very difficult to know what to do for the best.