I had kind of an inverse experience a couple years ago (pre-VS 787). We were put on VS A340-600 from Delta, and had to battle to get on Delta metal (newly refreshed/relaunched 767-400).

the whole VIPR re-accommodation system (built by Delta but now used by VS) blew up - not human error - but handled poorly.

ultimately Delta gave us $1200 in comp - Delta credit - spread across 4 people. Our flight cost was low - $1500 per FC/D1 seat one way - for comparison.

it took a month to sort out during the holidays.