I have a question regarding my wife's job.

During her pregnancy, she was informed that her contract will be terminated after her maternity leave. The three months notice starting the day after her maternity leave. So far everything's correct.
My wife was working 40 % before and has accumulated around 7 weeks of vacation. The idea was to save holidays from last year in order to prolong her maternity leave this year.

We are not sure if the company handles her vacation days correctly. Here is what she was told will happen. She is released from work over the whole three months, but needs to be available for request from the company. However, she has to "pay" for it, with her holiday account.
She did some research any it seems that employers can do that, if they inform the employee well in advance (6 month) in order to give her time to look for a new job.
In her case, she was 30+ weeks pregnant and later then in maternity leave. Can she be expectet to go to job interviews in this phase?

We doubt that and question why her holiday time isn't paid out.