UPDATE: According to Verge reporter Julia Alexander, Disney denies this report, saying it is “completely inaccurate.”
Just to dismiss what you’re thinking, no, it isn’t because of accusations towards Jeremy Renner. Before reading this I myself thought it would be because talks with Hailee Steinfeld fell through. Instead, Charles Murphy claims that production has been delayed because of changes to the future of the Marvel Cinematic Universe. Not a script rewrite, but that Marvel Studios wishes to introduce plot points for the current ongoing narrative before Hawkeye.
However, in hindsight, this delay shouldn’t be a surprise, especially since not two weeks ago, WandaVision was pushed forward an entire year and Ms. Marvel will be moving into production in April. This could also means, as Charles points out, that it will allow Hailee Steinfeld to be available for the role.
But, what could be so important they want to establish these plot points before Hawkeye releases on Disney’s streaming service?
Personally, I believe it will be to more properly set up Young Avengers since Speed, Wiccan, and Ms. Marvel will then be established before Hawkeye. Making way for Kate Bishop as another member of that time. This could also tie into Charles other report about Ant-Man 3 involving the Young Avengers too.
Source: Murphy’s Multiverse