Purchased in early March 2022:
SFO-ATL-SCL on 02/01/2023
47,000 miles for SN (Comfort+)
Then paid USD $499 for D1 for ATL-SCL (promotional upgrade on Delta.com)
Same for return leg ten days later except D1 upgrade for SCL-ATL was USD $599.
ATL-SCL-ATL is on the older 2-2-2 A350s (from LATAM) but value was well worth it for me.