I'm seeing the following:
4 flights- TB47 and TB48 Air temp -10 C, start battery temp 15- 20 C, flight temp after 1 min hover 25 - 35 C. Total flight times have been about 10-12 mins at 50% landing voltage.
12 flights- TB47 and TB48 AT -13 to -15 C, SBT 15- 17 C, 1 min hover T 20-30 C, 10 mins flight time to 50 % note: one flight where pack temp was only 20 C at end of flight was due to me intentionally flying without a battery insulation sticker to see the effect.
1 flight- TB48 AT -24 C, SBT 15.6 C, 1 min hover T 20.5 C, 6 mins at 60% landing temp was 20 C. I noticed the camera gimbal felt slow to move at this temp, didn't investigate this further as it was too bloody cold for me.
Most of the flights have been with iPad Air 2. I have not had any issues with iPad shutting down to cold. With my samsung tab s I've had it shut down due to cold on half the flights, but it wasn't fully charged when starting flights.
The RC battery has no had issues with cold and i keep it warm while switching packs between flights, warming up. I leave the I1 outside between flights. As soon as I bring the I1 inside the metal parts get some condensation on them so I have been putting it in front of a slow fan to help it dry out.