You need to push back on Delta again. They changed your itinerary, they need to rectify the situation. You can't get from one gate to another in ATL in 5 mins. and you will probably be going from one terminal to another. This means that you will have to get off the plane which usually takes about 15 mins., unless you are sitting in the front, get to the subway, which is in the middle of the terminal and if you have landed at Gate 35, it's a long walk, then go down the escalator and hope that a train is miraculously waiting for you. Get on the train to your terminal, get off, go up the escalator, get to your gate, which is always the furthest point from the escalator! I get the same argument from Delta, that if everything is on time, you have time to make your connection. Once I explain to them that even if flights are on time, 20 mins. is still not enough time to get from the C gates to the A gates, they relent! I have flown regional jets out of Northwest Arkansas for the last 3 weekends and there hasn't been a Delta flight on time yet. The weekend of July 29, my flight was delayed from XNA to ATL which meant I was going to miss my connection to MCO and the later flight was booked. I had Delta switch me to AA through DFW. Everything was on time and I made it to MCO, a few hours later than expected, but at least I got there. Delta will work with you, you just need to get through their standard procedures and be insistent!