AA 353 then 8C 1231 at Miami
Boston → Miami → San Juan
Timetable, Miami time
18:29AA 353 from Boston at the gate
15:008C 1231 to San Juan leaves the gate
20 h 31 apart on the timetable, overnight
8C 1231 leaves 20 h 31 after AA 353 arrives on the timetable: more than half a day, so not a connection we count.