Although the branch itself is seamless for me (suggesting that he does have the seamless flag set), the video is a little bit laggy for the first second or so afterwards when running from disc on the ps4. No other issues with video throughout the film. So there might indeed be an issue with the in-time, but I’m not sure.

As far as the other flags go, I’m not sure he needs to go hacking around with BDEdit, unless he really did forget to set the flag with the software he’s using. I know you’ve done quite a bit of analysis of some of these flags in commercial discs, Valeyard, but it turns out to be quite simple to set up seamless branching with the right software. Thanks, Williarob, for the help with that. It might be of interest to you, Valeyard, to test out the software in otherwise compiling identical images with the seamless flag set vs. not set, to see what the result looks like in BDEdit. PM me if you want to discuss that further.