A possible alternative solution for those sites hosted at WP Engine. It might be possible to replicate the updater on the client side.

It’s 4AM where the author’s at. If you’re awake and looking, maybe try it? Contribute some feedback?

https://github.com/balazsrm/wp-local-updater

#WordPress

GitHub - balazsrm/wp-local-updater

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@alex
I got a 404.