Yes. Go to court and say, "Your Honor. he knew what his income would be like in 4 years, but still wanted to claim the kids the first 4 years only. Since he entered into the original agreement fully aware of the consequences & his future income, and this whole complicated scheme was his idea in the first place, I ask the court to deny his motion and leave the dependency exemptions with me for this & future years. He should not be able to have his cake & eat it too."