She's playing a power game. The simple fact is that she will continue to do this as long as she has primary care. Nothing is likely to change unless you take that power away - and given the history of "3 years it has been 80/20 all him", that is exactly what dad should do. It is by far in the best interests of everyone to return to this stability and to do it formally. Will that get her to wake up to herself? Who knows, but if it does, then that's a bonus.
If she rejected mediation, then you can draw up all the proposals you want - I don't see her agreeing to any of it. You could threaten to go to court and even threaten to seek full custody if she doesn't at least start co-operating - but given her "Game On" attitude, I seriously doubt that it would have any effect at all. And that's the whole problem - she's treating all of this as game to begin with; she knows she's winning; and she knows it's getting to you and dad.
That in itself is a reason why dad must have a formal arrangement in place. If she takes off with the kids, then it will be much easier to get the court to order that the kids be brought back and there's a high chance that they would end up with dad full time as a result.
I certainly would not be offering or agreeing to 50/50 considering the way she's been behaving under those terms already. The primary goal should be to return the kids to the stability that they had before mum let the roos out of the top paddock - and this is what everyone should be focused on.
That's all we want is something in writing that gives the kids a bit more stability example. She wanted to have the kids back because she wanted them back and she would tell the kids that daddy won't let them see their mum if we didn't agree to it. They were due to go back to her as normal the next morning. The issue we had was that they didn't want to go back on his night and were upset about it as they really love their dad. My daughter had them that day and they kept saying to her it's Dads night why do we have to go back to mum's.
Also so we don't get messages the night before drop off saying I won't be home in morning so you will have to take kids to school. This is difficult as we both work and we would just like a bit of notice.
Yes and easier to get them back if she takes them out of state. Before I came on the scene she would constantly text him to have the kids majority of the time because her words she can't handle them or she wanted to go out and party. she wouldn't even speak to them at all during their time with their dad. It has gotten worse since I came on the scene. I know she is jealous and threatened. we will look into primary care just frightens me that he might lose time with them as she is good at making things up.