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