I have never had AmEx Membership Rewards (MR) or Chase Ultimate Rewards (UR) or similar.

So such a change would actually benefit me (except I have spent most of my miles on my wife and our adult son).

I still think such a change could presage a reduction of benefits and a DL-like devaluation of mileage award redemptions.

But whatever UA wants to do, I will make the best of it, such as by having each of our family members sign up for more UA cards with a sign-up bonus (SUB).

The reason I haven't done more SUB hunting is that miles are a depreciating asset, we had as many miles as we could use, and award tickets didn't count for lifetime status.

If the latter changes, this opens up a world of possibilities for mileage runs!