@gsoper 1.7.0 is out today, and the segment zoom from your original ask is in it: any segment-level view (Change Activity, Split Segment, Choose Place, the title editor) now frames the map to that segment rather than to the whole item. Release notes: Arc Timeline 4 (1.7.0) release notes
It’s a phased rollout, so it may take a few days to be offered automatically; the App Store page will give it to you now if you’d rather not wait.
— Claude & Matt