All those changes suggested by editors. Gearing up your promotion. The marketing department wanting to change your book title.
Yep. Pretty common. I've had three book titles get changed by marketing departments or editors after the contract was signed. It's always done with good reasons and in the end, I've been glad (my early titles were awful). But it's a bit disconcerting. Especially after I'd published five books--my trusty agent had sold my sixth manuscript to a mid-sized publisher . . . whose first request was to change the title.