No, blue is scheduled to operate 24 hours a day.
If you take it out of the pool, you might have incoherent values. Indeed, blue takes a measurement every hour and sends it to the servers of Riiot Labs to be analyzed.
However, blue is not designed to operate when the water temperature is below 5°. Please make sure to take it out of the water and put it in standby mode during the winterisation of the pool (please refer to the procedure in the operating instructions).