You need to use AC every week or so even in winter.
However, like you say, when you switch it off the vents chuck out ALOT of steamy air into the cabin.
To combat this turn off the AC about 10 mins before journeys end.
Turn heat up.
It dries out the moisture in the system into the cabin.
Most then escapes when you open the door.
When you start the car next day with no AC you'll have ALOT less condensation thrown outta the vents.
Back on topic.
I'm finding the blue indicator dot takes a week to go pink.
Followed microwave instructions and it's blue and ready to go.
Minimal hassle.
So far I'm quite happy with it.