Divorce and HCBM

Long story short. My ex wife and i were divorced in september of last year. i have had a surplus of parenting time in the time since it was final according to the parenting plan. The planned schedule on paper is odd. The parenting plan states that week one is mine.. i get my kids wednesday evening at 530pm to sunday evening at 6pm. Week 2, i get them wednesday at 5:30 pm to 6:30am thursday, and resume on thursday evening at 5:30pm until friday morning when the kids are awake on friday at or before noon. And then they go to her... and this alternates. Thing is.. thats not what happens.... she has demanded i keep them every full thursday and friday for every week...for mine and her weekends. Shes belittled me and stated that i dont "want" my kids when i tell her that is not the agreed plan....I realized this and got an attorney and she has been served for full 50/50 custody. NOW after being served from my lawyer...shes trying to go back to the papers and pay for childcare for those days (which goes back to september last year... i have kept them every thursday and friday since then)shes asked me to keep them. Would i be at fault for refusing to take them to a sitter vs me keeping them on extra days that i am able to? She called me out of nowhere after being served papers and asked me what sitter i was taking them to and i said theyre not going because they stay with me as they have been for months(which i pay for)....my mom helps too and she finally offered to pay her for her time on my exs time with the kids. Anybody with legal advice? I pay $1100 a month in child support already and dont want to step outside of legal bounds