Modifying type of vacation document [2.x]

It is possible to modify type of vacation document while editing vacation type. This process however may not be trivial.

1. Daily only → Daily or half-daily and Daily only → Daily or hourly conversions
This is the simplest and non-problematic conversion. There are no special, additional actions to take:

2. Daily or half-daily → Daily only conversions
If any user has half of day in their vacation days, then administrator has to specify whether available half day becomes full day, or is lost (1)

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)

5. Daily or hourly → Daily or half-daily conversions
If any user has available vacation hours, then administrator has to specify amount of time to change to available half days (any available minutes will be removed) (4)