On 1/31 Delta flew a 763-300, flight 8820 from NUW, Whidbey Island Naval Air Station in the San Juan Islands nonstop to Narita. It left NUW at 1040 PST and arrived at a ramp gate in Narita at 1342 Narita time. The runway at NUW is a nice 8,000 feet. May have been a ferry from a military charter into NUW or a new charter.
Also on January 30 and 31 flight 155 SEA-NRT operated in a 747-400 each day. The return flights on January 31 and February 1 operated as scheduled in 330-300's This was likely an equipment movement needed to upgrade flights 578-579, NRT-HNL-NRT from a 330-300 to a 747-400. But why two days in a row?