Ex wants to change weekends?

Me and my ex Have a pretty decent co parenting relationship. We have 50/50 custody of our 9 year old twins. My current partner also has a similar co parenting schedule and she worked towards changing her schedule to match mine specifically for some summer travel were doing both alone and with the kids

My Ex and her new boyfriend are on opposite schedules and she wants me to switch weekends with her so it better aligns. I have no issue her request it just throws a lot of planning into chaos as me and my partner are pretty avid travelers and adventurers but I also want to be fair to my ex as well. Im not sure what the compromise is.. Any advice anyone else deal with this?