American Airlines had a longstanding policy for giving certain benefits to their customers who book full fare Economy Class tickets but it now cutting back on a very valuable benefit.
American had also previously cut back the benefit of AAdvantage Elites to receivr complimentary upgrades to domestic First Class on full fare tickets.
You can access Americans Website for Main Cabin Extra here.
Buying a flexible ticket in a full fare booking class but some corporate contracts as well as government and military fares do book into full fare classes which always allowed the ticket holders (so far) to get at least a bit of a side benefit for the often big bucks involved.
Of course one would imagine that given the rather generous access policy for Main Cabin Extra anyone who buys full fare ticket on a regular basis is at least a low tier or mid tier elite member if not higher and therefore would have access to MCE regardless of this change.
This will hurt travelers who book American Airlines in full fare on a whim because their company decides the flexibility is important or the deal they have with American dictates that all their fares book into a full fare class and then a discount is applied.
Having a Y/B class (full fare) ticket as a regular customer is rather rare though not uncommon. I don’t like when such things get sneaked into the fine print and all of a sudden customers find themselves on the short end of the stick without proper publication such as an email.