I thought I would share some tips on booking SCL-IPC-PPT using miles.
First, or SCL-IPC, it really makes zero sense to use miles on this segment (90K AA miles roundtrip). A roundtrip in business class is available or roughly $525 if booking through the LAN Chile web site (
https://www.latam.com/es_cl/). Just be sure to read carefully and translate anything you don't understand. Used a US credit card with US billing address - no problem.
For IPC-PPT, just keep checking on BA.com. 7 seats opened up on a Sunday morning (roundtrip) and disappeared before I could book it on Tuesday. I kept checking, and the next Sunday seats opened back up. Booked four award tickets for a total of 120,000 AA miles.
So, in all, 60K roundtrip award from US to SCL + 550 roundtrip SCL-IPT + 30K roundtrip award to PPT is not a bad deal. Compare 30K +15K +40K +250 if you would rather return to the states on Air Tahiti Nui.