So as an update to how this itinerary is evolving post-ticketing, LAN cancelled the IPC-LIM route from April through December, requiring a connection through Santiago. LAN protected me on a flight with an overnight connection to a 6:40am departure in regional Y+

The wonderful AA RTW desk called me to inform me of this, and I was initially prepared with ExperFlyer knowledge to be put on a flight two hours later that was on an international configuration 767. The wonderful Meredith, head of the AA RTW desk, came up with a better idea, and put me on the following day's once weekly morning flight out of Easter Island so I could connect to Lima without spending another night in Santiago.

Then came the issue of my ticket now having 17 segments and wonderful British Airways not accepting paper tickets

Meredith had a perfect solution worked out, she will hold the reservation IPC-SCL-LIM for me until I fly my first few flights leaving IPC-LIM officially as an open segment at this time, and then reissue the ticket after I fly the first few segments of the ticket with the IPC-SCL-LIM segments included.

Wonderful customer service, AA!