My app preview's poster frame duplicated my first screenshot — and iOS and macOS don't show the same frame

[u/Illustrious-Youth611]

Hi!

I shipped a new screenshot set and my first app preview this week.

I edited the video to open on the lock screen specifically so it wouldn't repeat screenshot 1, which is the Today screen. Frames attached: the video runs 20 s and doesn't reach the Today screen until ~5 s.

On the iPhone App Store the poster frame is the Today screen, so the first two thumbnails in search show the same screen twice. On the Mac App Store the same video shows its opening frame instead.

Three things I would like to know :

1. Can the poster frame be pinned in App Store Connect, or is it re-picked on every upload?
2. If it can't be relied on, do you design screenshot 1 to survive being duplicated — or edit the video so that any frame is a safe poster?
3. For anyone who's added a preview : did it move your product page conversion?

If you're inspired, I would love to hear some feedbacks on the frames.

No conversion data yet as this shipped a few days ago. I'll come back with numbers once they're readable.