Running v22.5 beta (build 49 I think).
Opened v22.4 sequence (in a production) + hit render all.
Watched back + one file is media offline. Hmmm. Bit annoying I wasn't warned/prompted.
Found clip, went to relink, it found file but reported that it wasn't compatible.
This is a screener so it's MP4 plus it has (bracket symbols) in the name.
Converted to prores proxy in shutter encoder + it relinked fine.
This isn't the only MP4 in the project (lots of A7s C000x.mp4) mind. But there's something about it v22.5 doesn't like that v22.4 was fine with.