I am sure there is a thread on this, but the FT search function is awful, so I apologize...

I currently have a flight on United booked friday early AM connecting thru EWR to international on Friday 11/7....given the latest news from the FAA regarding airspace limitations possibly beginning Friday, I am concerned.

My question is, if i book a refundable fare on Delta thru ATL when exactly do I have to cancel this by to get a full refund. I totally intend to take the United flight and would cancel the Delta flight ~30-60 minutes prior to departure assuming no issue on EWR flight. Appreciate any help here...thanks.