Use of "variation" tab in Area Settings

[manolof]

Hello there!

I was wondering if someone could help me with the Variation tab inside Area Settings.
I have a case scenario, but can't figure out the best setting for this.

For my enclosure I would like the temperate alarm to be set lower during the "winter" season, and back to normal during the warm season.
For this, I would like to use either a dateTime, or a JSON file with a list of dateTimes.
Example:

With the current documentation, it is not clear what the format for the "At time" should be, or for the other options either.

Any help much appreciated!