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3. Daily or half-daily → Daily or hourly conversions
If any user has half of day in their vacation days, then administrator has to specify amount of hours to add to users, instead of half days (2)
4. Daily or hourly → Daily only conversions
If any user has available vacation hours, then administrator has to specify amount of time to change to available full days (any excessive time counted in minutes will be removed) (3)
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