A re-encode's playlist is now the whole film on a fixed 4 s grid. A segment that isn't on disk and isn't coming soon moves the encode there; runs stop short of segments already made, and gaps are filled after. Every run is cut the same way (-ss, -output_ts_offset start+10, frag_discont), so segments from different runs join. Repackaging keeps its growing playlist. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>