I'd be bothered in your shoes as well. It is a bit weird to me that L said something about being "predictable". To me it sounds like you were/are not really able to predict the times when she's gone. You can for the public holidays, but if I understand correctly, the other vacation is more or less "when she/her family want it". For contrast, my T always takes off the exact same times of the year: two first weeks of school vacation in Summer, the first week of school vacation in winter, and the two weeks right around Christmas and new year. I think it's reasonable for you to want to know at the start of the year when she's going to be gone. Even if it were just for being able to plan your own stuff.

The other thing that I would also strongly react to is the taking the whole week off when there's a holiday. That adds up to a lot of time, for me that would probably be too many instances. Though I don't know how it would be if we did virtual those times. All I know is already with the few holidays that hit my session each year, I'd wish those days didn't exist...