MilesBuzz! - Abundance of UA 777's at PAE

I was up at Paine Field tonight (Home of Boeing's Everett Plant), and noticed 4 777's. Two of which, have been there a few weeks, and are at Tramco, with all the engines removed, fairly typical to have 1-2 in here at a time. But, the other two, were sitting on the tarmac opposite Tramco, just as if they had been parked there. I got three tail numbers N224UA, N225UA, N226UA, but was unable to see the last one. Now, it's possible that all of them just happened to be for service at the same time, but, it does seem sorta odd, as if maybe UA is "storing" them up here. I don't think these were awaiting delivery from Boeing, as they were not on the usuall Boeing property, but rather airport tarmac, usually occupied by any military aircraft, such as the B-52 sitting up there. Any thoughts?

They may not have been delivered. They are still shown as registered to Boeing, and appear to be 2 pair of consecutive SN's.
N224UA SN 30225
N225UA SN 30554
N226UA SN 30226
N227UA SN 30555

The rest of the info is the same for all:

N-number : N225UA
Aircraft Serial Number : 30554
Aircraft Manufacturer : BOEING
Model : 777-222
Aircraft Year :
Owner Name : BOEING COMPANY
Owner Address : PO BOX 3707
SEATTLE, WA, 98124-2207
Registration Date : Not Specified
Airworthiness Certificate Type : Not Specified

Sounds right...Boeing did not spent the big $$$ to place millions of bucks worth of turbo fans on them. They may sit there for years as white tails...almost white...

I actually found a web site the other night, but can't find it now, that was done my a United Airlines FA, and had a listing of every 777 from the tail number, and delivery dates, and things associated like that. All 4 777's numbers I saw were on his list, that was supposed to be delivered in December, but was pushed back to late January. Interestingly, according to the FA on my flight from DEN-TPA announced quite a few times that starting Feb 1st, UA will be offering NS service from DEN-HNL and back, on, 777's.