DP has 2 children from previous relationship. ExW isn't known for her ability to reason, and so here we are...
Childcare is 50/50 on a 2 week rotation with set days each week. It's been this way for a long time (more than a year) and works well for the kids and parents (90% of the time anyway!).
ExW has decided to go on holiday with her partner at short notice. She messaged DP asking him to have the children on her set days (not swap days, have them in addition to his usual days) and stated she had already booked the holiday. This would mean him having them 10 days in a row.
DP said no as 1) it's too short notice and 2) he's sorted work around his children months in advance and can't be easily changed (nature of his work means it can be incredibly difficult to arrange any swaps at short notice).
ExW isn't open to making the days up elsewhere. Just in the last 6 months, she's done this several times at short notice and it means DP or I have had the kids nearly an extra month. There's not even been so much as a thanks from her, even if it has been me picking up the extra childcare.
So, AWBU in saying no and DP finally putting his foot down at her piss taking, or is she BU constantly making plans during her childcare days/ nights and just expecting DP to rearrange his life to suit her?
So as not to drip feed, this is a woman who ran to CMS when 50/50 first started and claimed DP was only having the kids 2 nights a week. Prior to 50/50, DP had the kids between 4 and 6 nights every week and still paid her CM (more fool him, I know!).