Same in Switzerland, formal education starts at 6, there is kindergarten which is not compulsory,but recommended.
So there wouldn't be further demands for childcare, just less pressure on children in the reception years of 4-5 years old. Kids here go on hikes, sing songs, play, cook, learn how to listen and interact at that age.
At 6 they are then expected to become formal - desk based learning, so a big switch over.
One thing they'd need to take into account is class sizes though. With less years dedicated to early years education you can't really have a class of 34 children (as was the size of my DS class before we left the UK) I'd have thought. Class sizes here are generally capped at 18 so there is plenty of teacher:pupil time.