Buddy of mine went on holiday for a weekend.
Evony messed up and he could not log in again, he had to create a new account to play. He tried everything with evony and the issue was not resolved.
after a year, his city's, 9 of them still sit in holiday.

Most likely a glitch, caused by the merge, if the dude is lucky and persistant he may get it back, but expect to see it there forever.