I do not know anything one way or the other, but if it was scooped DL/AMEX maybe trying to determine who leaked their internal information and then determine if they still want to go forward, hold off for a bit or rethink what they want to do.

Moreover, you assume that DL/AMEX cares that they were scooped, they maybe saying internaly, we will announce when we are good and ready and this reddit post is not going to alter our plans. They could also be watching to see if an aviation journalist (there are a number of ones) decides to go forward with the story and then and only then will they announce the change earlier than they (DL/AMEX) originally planned. I am not a business person, I am a physician (which means a lot of things, but chiefly, I am really really bad at business), but my wife is a business person and she said a reddit post does not carry much weight in the corporate world, a journalist carries far more weight.

It is also possible that it was an idea that they (DL/AMEX) decided to not go forward with and the leaker/scooper (who on the reddit post iirc said that they were an ex-employee) did not know that DL/AMEX decided to no go forward and DL/AMEX are not going to respond at all.

It is also possible the reddit poster made it up completely and DL/AMEX are not going refute some post on reddit, going back to the whole a reddit post does not carry much weight in the corporate world.

Again, I have absolutely no clue oneway or the other, I just have a Platinum Amex and would lose a benefit that I presently enjoy and make use of.