Https://businessstrategy.louisville.edu/hc/en-us/community/posts/37627613725843-Check-DELTA-Flight-How-late-can-you-cancel-a-Delta-refundable-flight https://businessstrategy.louisville.edu/hc/en-us/community/posts/37627613725843-Check-DELTA-Flight-How-late-can-you-cancel-a-Delta-refundable-flight