I cleaned out my PanAm account with two first class seats from New York to Geneva in the Fall of 1991. The return leg was the final PanAm flight on that route.

What little I had left went over to my then existing Delta account which begins 0623. My wife's miles went to Delta which opened up her 400 account.

I seldom fly Delta for domestic flights and use the FF program as a place to dump Amex Rewards miles for non-business international travel.