B6 2120 then DL 5831 at Boston
San Diego → Boston → New York LaGuardia
Timetable, Boston time
05:34B6 2120 from San Diego at the gate
18:00DL 5831 to New York LaGuardia leaves the gate
12 h 26 apart on the timetable
DL 5831 leaves 12 h 26 after B6 2120 arrives on the timetable: more than half a day, so not a connection we count.