Let me throw out another example of what I was talking about....just so that everyone understands.
If dad's every other weekends continue throughout the summer, on top of his 5 weeks, then it would be literally possible for dad to take every "week" to cover one of mom's normal weekends, tack his weekend on the end, so that he got EVERY summer weekend. That would leave no summer weekends for mom and the child to spend together, and would leave no opportunity for mom to vacation with the child, even if mom couldn't afford to go away for her vacation, and instead preferred day trips to fun places.
Personally, my preferred summer schedule is every other week or every other two weeks. That gives both parents uninterrupted blocks of time with the children...and also allows for things like the children spending a week with grandparents as well as multiple choices for vacation time of their own.
So OP...if you end up going back to court, try getting it put in place that summer is every other week or every other two weeks. Then you don't have to worry about extra days getting tacked on.
If its written correctly then the timeshare would be "fixed" and there would be no need to "inform" by certain dates.
Example:
Summer break will include every other week for the parents. The ncp's first summer week shall commence at 6:00 PM on the first Friday after school releases, and the weeks shall rotate from that point, every Friday at 6:00 PM until the last Friday before school commences.
If the last week of summer visitation is with the CP, then the NCP will receive the first weekend after school starts, and the school year rotation will commence from there. If the last week of summer visitation is with the NCP, then the CP will receive the first weekend after school starts, and the school year otation will commence from there.
That's clear, unambigious and allows both parties to plan their summers without having to worry about "notifying" each other.
If a two week rotation is better, then do the same thing, only base it on two weeks instead of one. However I don't think that two weeks works as well. However, if both parents want two weeks for vacation, then a proviso can be included that each parent gets to choose to take one week of the other parent's time for "vacation"...but then you get back into the whole "notification" bit.
Of course summer visitation deals with Memorial Day weekend (in some states) the 4th of July and Labor Day (in some states) and Father's Day.
However, Father's day can be dealt with by indicating that dad gets that day..and the rest of those holidays could just fall as they may.