Or your experience could be like that of Susan Orleans as reported in The New Yorker. She writes:
“My first book was acquired by two people I will call Editor A and Editor B, who ran a small imprint at a big publishing house. We had a great lunch to celebrate.
A few months later, Editor A left book publishing to become a newspaper writer. Editor B became my primary editor. She and I had a nice lunch to talk about my book.
A few months after that, Editor B was promoted to publisher of the larger house—let us call it Publisher W—that owned the small imprint. Because Editor B—that is, Editor/Publisher B—now had too many duties to edit my book, I was assigned to Editor C.
Read more here.
I'm lucky - I've never been orphaned. I was talking to a friend recently who is on her third editor for a book - her first two were let go. I would feel whipsawed.