Back in 2017, Apple TV 4K users cheered when selected films in their iTunes libraries started receiving Ultra HD upgrades at no extra cost.

Now, it appears the opposite is happening (albeit unintentionally), with both purchased and unpurchased 4K movies being downgraded to HD thanks to an alleged bug, as reported by 9to5Mac.

Originally believed to be an issue only affecting Warner Bros. titles, the list of downgraded movies has since extended to productions from other studios, including MGM, Columbia, Twentieth Century Fox and more.

One user has compiled a list of downgraded titles over on Blu-ray.com's forums, which includes the following:

Fast & Furious 6 (2013)

Harry Potter and the Deathly Hallows, Part 2 (2011)

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