This appeared to be an widespread issue for us. We believe Images users uploaded were being rotated before we received them. In our testing after we disabled this feature users uploads were no longer rotated.
We appear to have had two distinct problems. Images stored in our static storage were rotated. These were images uploaded via an CloudFlare-fronted service. The second issue is every image we served out was rotated again. So some images ended up fully upside down having been rotated twice by cloudflare. As mentioned above turning off this feature and flushing cache has fixed the issue, except that uploads that have happened in the last day or two have had some that were rotated. This was such a sudden and widespread issue across our 500k user user base that we don’t believe suddenly all our users were uploading rotated images.