Custody Orders: To follow or not to follow

The current custody order is 50/50 both physical & legal. The judge stipulated that the ex will have the children during the SUMMER if Father has military training. The question is, if he has training during the WINTER, do we have to allow her to have the children? The divorce was dragged out and the kids have lived in our joint household for over 2 years, they see my kids as their (annoying) brothers and they have a sibling on the way. They dislike when the routine is disrupted and would prefer to continue with the schedule even if their dad is at training. We would like the schedule to remain static during the school year to give the kids stability, something that is lacking over at their mother’s home. Should we stick firm to not allowing her to have the kids during his 2 week training since it taking place outside of the court ordered SUMMER? She was denied ROFR (Right of First Refusal) by the judge. She is constantly trying to use the verbiage of the order to manipulate time share. We don’t want to stoop to her level, but in this instance we feel that the schedule remaining intact is a good reason to push the verbiage that the judge used. Specifically she only gets them during the SUMMER/

To be honest, if the custody arrangement/agreement that was finalized in the divorce states that she only gets them for summer and summer only, then no you would technically not have to give them that extra time, unless that is what you have agreed upon.