I had selected seats 1K and 1J on the LAX-AMS flight on the 747 Combi when I ticketed this trip in August. (The trip is to take place in 12 days).
I've logged onto my account from time to time since then, and gone into the select seats screen so I could check if there'd been an equipment change or if I lost my seat assignments, etc.
I just checked and it's still showing the 747 Combi, and by our names it says:
01J World Business Class (confirmed) and 01K World Business Class (confirmed)
BUT, it no longer gives me the option to select seats which is how I'd been pulling up the seat map. Instead, to the right of the screen it shows:
About Your Seat
And when you click on that it shows:
Choosing your seat
Unfortunately it is currently not possible to select seats.
During check-in you can again choose or change seats, and reserve seats in the Economy Comfort zone too (if available).
You can check in from 30 hours before departure (from 24 hours for flights to and from the United States).
So it this anything to be concerned about?