I just spoke to a KLM rep while trying to select a seat for a CPT-AMS leg in October. Although the KLM website lists it as a 772, the configuration as described by the rep is different than what is shown on the KLM website or seatguru as follows:

Rep description:
777 (Flight 598)
C= 2-2-2; Rows 1-5 and 10-13 (same as DL 772ER)
Y= 2-5-2; not sure which rows (but configuration not same as any on DL, NW, or KLM 777 per Seatguru)

KLM Website and Seatguru:
772ER
C=2-3-2; Rows 1-5
Y=3-3-3

773ER
C=2-3-2; Rows 1-5
Y=3-4-3

The rep noted that they may be acquiring another carrier's metal due to the DL/NW merger, but I can't find any with the above configuration on KL, DL, or NW. Any ideas?