I have no idea. It could well be a glitch and no big deal. But Monkey Miles tweeted about this and I see it myself in my own account.
Update: Amex seems to be conforming it is a temporary glitch and transfers will be restored soon
— Monkey Miles (@MilesTheMonkey) October 29, 2019
Logging in, sure enough there’s a missing space where it should be.
Note that if you direly need to transfer Amex points to book a BA flight, you can still just transfer to Iberia Avios or Aer Lingus and then transfer via Avios.com. Of course you can still transfer your Chase Ultimate Rewards points over as well.
More when I know more…
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