Just happened to me. I had a USH-AEP-SLA itinerary a few months down the line. Last week they changed it to USH-EZE/AEP-SLA, with less than 3 hours between the EZE arrival and the AEP departure. No way could I make that. I called the Miami number and they changed it to USH-COR-SLA for free. It was surprisingly efficient. Hopefully it won’t happen again, but I’m bracing myself for further changes.