Have you implemented annual leave (vacation) in Japan?

I am working to implement Absence Management in Japan and am at an impasse in terms of how to implement the annual leave (vacation) to match Japanese law.

The law specifies that a certain number of days are given to an employee at the first of a year (front loaded). Of the days that are granted, the equivalent of 5 days can be taken in hourly increments, but they don't have to be taken in hourly increments and can be taken as full- or half-day leaves as well. When an employee elects to take some of their annual leave in hours (has to be full-hour increments), then the annual leave balance of 'days' should be reduced by 1 and whatever remaining hours from that day aren't