Originally Posted by rmadisonwi

Domestic narrowbody equipment assignments for flights 6+ months out are really just placeholders. When they get closer to finalizing the schedule and consider the best overall equipment rotation, then they will update with finalized equipment assignments.

There’s no way they would practically know about engine issues 6 months in advance. But, given recent guidance on expected equipment deliveries, it’s likely that they will have fewer new planes (both Max and Neo) for various reasons, and if they put placeholders in the schedule for those newer types, but then have to revise for reduced availability, those sorts of swaps will happen when the schedule gets finalized.