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Answering "when is transcode_import planned": it is the remaining third of 10(b), but it must not be next, and both reasons were learned on the thumbnail side rather than predicted. Format has to move into `variant` first. Transcodes are inherently multi-format and `variant` is keyed on size alone — the same gap found in 10c that keeps JPEG thumbnails on the sidecar. Importing before that means migrating into a schema that cannot hold the data without collisions across formats. One migration unblocks both, which is the argument for doing it before either. And step 7 must precede the import. ImageTranscodeService writes only its file-keyed disk cache today, so the import would run against a cache that is still growing and never reach an empty tail — exactly the trap persist_rendered had to close for thumbnails, where one of four render paths recorded a row and the tail could never empty. Order: format-in-variant → step 7 → transcode_import. Also records why the .skip markers are still open: a cached negative verdict has no bytes, so it does not fit a table whose point is pointing at a blob.