There can only be one profileType per month. A profileType can be active over many months.
ProfileTypes are now set on the 1st of the month. If a profileType is being completed for the first time, the profileType will be linked to the current month.
Before saving a new profileType, check for other occurences on the given time period. If occurences are found delete them, new profileType overrides them.
Introduce a new migration to make sure no multiple profileTypes can exist over the same month.