Sure feels like it. With Edgar Wright and now cast members leaving.
"Its a perfect script that we had to essentially rewrite entirely and recast extensively."
Also, the set-in-stone release date for this effects heavy blockbuster is now less then a year away and they've yet to shoot a single scene. Yeah, Marvel is definitely tripping over themselves here, but then again, this will be the first MCU film out after The Avengers 2, so no matter how much the release date slips or how muddled the movie might be, there's still a good chance it waaaaaay overperforms for being a friggin Ant-Man movie. I would say another sign of Marvel effing up is their seemingly dogged efforts to get a Dr. Strange movie together for phase 3, which seems like an ill-fit for the universe they've already created, and the fanbase seems to actually want more diversity for their super-hero-ing at this point. Captain Murica' 2, has a white guy front and center, but Scar Jo and Samuel Yell Jackson are the #2 and #3 stars in it, and it did really, really well for itself.