This question comes up a lot in the fall. Lots of threads on it. There are many cases where people have reportedly flown happily in brutal arctic cold. Obviously you want your battery warm and AC to be somewhat warm to start. But you also have to worry about the slight expanding and contracting of the electronic boards in the AC which may develop hairline cracks over time and ultimately cause a premature catastrophic failure. So I think the answer really depends on the level of risk you're willing to live with, both short term and long term.
Having said that, the coldest I've flown is 22 F with plenty of other flights below 32F. No problems during the flight or afterwards. AC is still flying.
Edit: Also, consider that if your AC is still under warranty, flying outside of DJI's stated temp allowances may give them a reason to deny an otherwise legitimate claim.