I am scheduled in AA912 SCL-MIA on April 9. DST ends on April 7th in Chile and they move clocks back an hour, putting them at UTC-4, matching Miami who is also UTC-4. If my math is correct, and I've double and triple checked it, since the flight is within the same time zone, if it departs at 7:40 PM and takes 9hr37m, it would arrive at 5:17 AM in Miami, not 4:17 AM. They are off by an hour somewhere.

Obviously, I'm hoping that the arrival time is wrong, and I'm arriving at 5:17 AM in MIA, which cuts my layover to 3 hours instead of 4. I assume no matter what, the departure time is correct and it's not really departing at 6:40 PM. I hope that assumption is correct?