Well, this is a first for the UK!
In the US, it is normal for Amex points to transfer instantly to airline and hotel partners. This is not the case in the UK, where it usually takes 4-5 days.
(The best transfer partner is usually Tesco, who can get Clubcard points across to British Airways or Virgin Atlantic overnight. The worst is Starwood Preferred Guest, who took 30 days to do a Lufthansa transfer for me earlier this year, and I know only move Emirates transfers once per week.)
However, I just did a transfer to Virgin Flying Club to benefit from the current 25% bonus I was targeted for.
When I did it, I got this message:
“Your Membership Rewards points will be transferred instantly to your Virgin Atlantic Frequent Flyer Account.”
I was, frankly, highly dubious of this! I logged into my Virgin account, though, and they were there. (This was only the base mileage – the 25% bonus miles were always meant to post in arrears.)
This is a fantastic improvement, and means that you can look up reward flights on the Virgin website and instantly transfer the points across from Amex in order to book.
This does not apply to all partners, though. I have no idea about British Airways, but having done a Club Carlson transfer this week I can confirm that those points do not go across in a hurry – I am guessing 4-5 days.