I've tried every way possible to stay in ATL longer (to meet a friend for lunch/dinner etc). When you SDC confirm your first leg, you're connecting leg will also changed to fit the 4 hour rule.

Example: LAX-ORF

Original flight
Delta 101 LAX-ATL 11:40am - 6:54pm
Delta 4166 ATL- ORF 8:15 PM - 9:54pm

SDC Option 1 (Leave LA Later)
Delta 152 LAX-ATL 1:00pm - 8:05pm
Delta 1503 ATL – ORF 9:30 PM - 11:06pm

SDC Option 2 (Leave ATL Later. Still within 4 hours)
Delta 101 LAX-ATL 11:40am - 6:54pm
Delta 1503 ATL – ORF 9:30 PM - 11:06pm

SDC Option 3 (Leave LA earlier, Leave ATL Later. Still within 4 hours)
Delta 61 LAX-ATL 10:25am - 5:35pm
Delta 1503 ATL – ORF 9:30 PM - 11:06pm

NOT SDC (Stopover over 4 hours)
Delta 560 LAX-ATL 12:55am-8:02am
Delta 1503 ATL – ORF 9:30 PM - 11:06pm