Some people using the Minimed 670G pump and Guardian sensor have recommended inserting a new sensor a couple hours beforehand prior to the expiry of their sensor they are using (a process they call “marinating” the sensor). In this way the sensor stabilizes well before you have to exchange it out with an old sensor.
I have tried this technique but with mixed results. It has worked beautifully lately but initially a couple sensors completely failed prior to the warm up period. As soon as I inserted the sensors into the transmitter, the green transmitter light did not blink as expected. Neither could the pump find the sensor. Maybe a bad batch?
Marinating helps the sensor signal stabilize quicker after the warm up period, although you still have to pay attention to upper thigh sites (they take longer to stabilize and can lead to major lows once the sensor stabilizes).