All International 757 Aircraft Now Have E+

The 763's must be UA's ghetto birds, which were configured for domestic rather than international operation, because I don't think CO operated any 763's. All of UA's international 763's already have lie-flat C seats, in the rather pleasing 2-2-2 alignment. Will all of the additional 763 conversions become 3-class aircraft (and therefore interchangeable with the rest of the 763 fleet) or are they introducing a new 2-class variant?

I assume that the 763 conversions will enable the 762 retirements, and essentially replace those aircraft.

Once the 787's start arriving, UA could potentially have some significant growth in the international fleet.

They are the UA domestic 763s.

They'll be configured in a two class configuration, with 2-1-2 up front, similar to CO's 767 fleet. They will have the same seat in the front cabin that's being installed in the BusinessFirst cabin on the CO 764s.

I am not sure if this is obvious to everyone else, but it says that the front cabin will be lie-flat BusinessFirst, does that mean that the legacy UA 757s are not being used on these routes and will not have lie-flat seats up-front?

That is correct. The sCO 752s have been in an international config for a while now. The sUA ones have not and almost certainly will not be converted to such.

Lesson for AA. Installing E+ should not take time

With AA's history of MRTC and LRTC, I'm sure they know quite well how quickly they can reconfigure a Y cabin.

The announcement refers to the CO fleet of 41 752's configured for transatlantic operation (which also offer selected domestic flights.)

Within the UA 752 fleet there are currently about a dozen aircraft which operate the ps (premium service) on flights between JFK and LAX & SFO. These aircraft currently have 12 lie-flat F seats and 28 C recliner seats. It's been announced that the ps aircraft will be converted to offering 28 lie-flat C seats, presumably the CO seats. I don't know if they will be converting the existing ps aircraft, or converting some other 752 aircraft for the new ps fleet, and then doing something else with the existing ps aircraft. Since quite a few of the ps aircraft have had the winglets added, I don't imagine they will be retired. I believe the mid-cabin galley will also be eliminated.