Mugwort oil spoilage and temperature

Neither the ambient temperature or putting the mugwort oil in a minifreezer affects it’s spoilage time.

Is this normal?

Does it actually spoil in the listed time if put in a cold environment? Because displayed spoilage time assumes a particular ambient temperature, and is not accurate in other conditions. So if you’re just looking at the display that would be why it is different.

I don’t know, it is less than a week old. The item description says that it will spoil in 4 weeks.
I’m about 1/3 through winter (91 day season).
The mugwort oil doesn’t say that it’s cold or frozen while it is inside my minifreezer (it is on).