It appears to be N501DN (Delta's first new A350-900 delivered from Airbus back in 2017) that is going to fly ATL SCL A359 first on 6/2/2022 (today). Still unknown on which route N575DZ (LATAM 359 aircraft) will be flying. BTW, it just arrived in MSP from SIN (a distance of 9900+ SM) without a stop, I would venture a guess that this flight was void of passengers, baggage, and freight - hence, longer than Airbus states that the plane's range is. Airbus's listed information sheet was probably with passengers and baggage and freight on board. 9900 SM is up close to the range of Boeing's B777-200LR's (which Delta had 10 of but retired all of them in 2020). Delta appears to be having this route (ATL SCL) using the A359 every other day, along with an A330-300 (or -900neo) on the opposite days. N576DZ is currently over at SIN and will probably be #2 into service with Delta. N574DZ will be number 3 (currently at SEA). 574, 575, and 576 are all Higher Gross Weight (280T) and therefore will have a slightly longer range than DL's first group of 359's.