I had a strange encounter with this message. Many months ago I booked an award flight for Mrs. Redtop on which the return went OTP-AMS-CDG (then a stopover). I logged in to look at it last month and saw it was a 40 minute connection in AMS and the message "You May Miss Your Flight." I called, thinking one of the flight times had changed, but was told that's what it had originally been, a 40-minute connection. (And note of course that these were obviously not DL flights, they were KLM/AF.)

However, somewhat surprisingly, they very slightly begrudgingly switched her to a nonstop OTP-CDG with no fee, which obviously hadn't been available for an award ticket when I first booked. So the story had a very happy ending.