You have 3 options (6 obsolete (Legacy)):
Use calendar: The model will use the calendar specified above when constructing hourly day type patterns.
Single Day type: The model will construct hourly day type patterns, using only one single day type for all days.
None Day type: The model will not construct any hourly day type patterns at all, transforming the model into a regular regression model.
Legacy options (obsolete): The rest of the options are related to the Legacy day type calendars, which are to be replaced by the calendars integrated into the Aiolos Forecast Studio.