https://www.indiewire.com/2020/01/benh-zeitlin-interview-wendy-1202205085/
The 60-day shoot took place intermittently between February and November 2017; Zeitlin reconfigured the story in post-production, as one editor replaced another, over the next two years.
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Even “Peter Pan” fans will never predict where “Wendy” is heading, and Zeitlin didn’t always know, either. He shot the movie so far off the grid that the studio had to wait around for updates.