I've commented on this before, but my employer has rolled out a hybrid model. It doesn't have a stated number of days to be in the office, though one day a week was floated verbally by the VP over HR.

I already know some managers will expect five days in the office with WFM by exception. People with kids will get more leeway to be home. Other managers will have zero expectations to be in the office. Individual employees will be subjected to the same policy but different supervisors.

The other thing is coming in the office a minimum will be a tacit acceptance that your career here is at an end. That's even mostly true if your supervisor doesn't care. Others will; enough will that a promotion or larger raise will get squashed. Expectations will be to be in the office three days a week minimum.

I have low expectations for the policy. I think it's going to create frustration. Management will feign disbelief that anyone could be frustrated, pointing out the words in the policy allow WFM while putting their hands over their ears and chanting "LALALALA" when anyone says "yes but the implementation isn't so generous."