It looks like it opened in the past week or so. It has gates in the 50s. A bit far away walk to the passport control area. UA, NW or any other late night arrivals should now stand better chances of getting a jetway instead of a bus transfer.

And the pier for gates in the 40s seems to have been closed .... for perhaps renovation? I just noticed it today.

I arrived about 10 days ago in the new gates via UA875, at the end of the pier. It is indeed quite a walk to immigration. Fortunately they have installed some moving walkways in the main transverse (N-S) corridor. My only question is: how long will the carpet stay clean? Thais are great at maintaining stone, ceramic, and vinyl floors, but are not very good with carpet... IMO.