child support order objection

My divorce was final in 1996.I have physical custody of our two children and we share joint legal custody.The decree says I have 200 overnites and my ex has 165.She and I agreed directly following the divorce that for the kids' stability sake she would have every other weekend and holiday and every third wednesday night.That totals about 70 overnights in a typical year.Her child support was set at$88 a month as she was on unemployment at the time and as far as the court was concerned she has 165 overnights.That is the way it stayed as I didn't want court involvement in our lives and I wanted her to be able to provide for the kids when they were at her house.I have seen where one parent is left with almost nothing after support comes out of thier check and I didn't want that.So for 13 years she has paid $88 a month.Kids have grown an are much more expensive now,she doesnt pay for her half of lots of things, she and her husband make more money than my wife and I so I have recently sucessfully petitioned for an increase.I sent in a letter, we had a hearing where we were asked; what is our overnight arrangement? we both answered to the referee 70 with her 295 with me ,Then we were asked;has this been the case for an appreciable amount of time? we both answered yes.The referee counted the days on the calendar and ordered the new judgement in the amount of $642 per month.
My ex has objected to this on the grounds that the original decree says 165 with her 200 with me even though we have never done this.
My question is this; under Michigan law, which will prevail in court the original decree or our long standing agreed upon and court testified agreement? Also ,the referee used the phrase "appreciable amount of time".Is there a guideline or precedend to refer to?

I guess this was too tough a question for everyone.

[Gbyte]

Yes it is a tough question. I would suppose she may be allowed to resume the previous schedule. Or...the order will need to be modified to reflect the current arrangement. It's going to be up to the judge.

Yes, it is a tough question to answer because nobody but the judge can predict which will be the one chosen to follow. Any answer here would simply be a hazardous guess. Sorry to say, but you are going to have to wait to see what the judge decides on.