It is common that many HRs will find out that employees' join date is the middle of the year, but the generation time of their leave balance is from January. (Click 「Leave」>「Leave Balance」>「Leave Balance Record」)
It is because the starting date of Leave Year is January 1st as set in「Leave Policy」, so from January 1st to the end of the year is a leave year for all employees.
Although the generating time of leave balance is January 1st shown in the page, but the actual pro-rated days are calculated based on the join date.