Plex Binding - player endtime issue

I have OH 5.1.3 running on a Pi5, attached to a local network which has a Plex Server (with plex pass).
Everything works as expected, apart from one channel ‘endtime’ which is documented as a DateTime value. While the player is running, it is supposed to show the time that the video file will end, but all I get out of it is NULL. I’ve used date values in several other things, and never had a problem like this.

However, if I link the channel to a String Item, the time and date is displayed, albeit in a non-standard format. I’m confused as to why this is happening, but what I really need is to get the endtime out as a DateTime.

I’ve attempted to workaround it by selecting a substring of the desired data, and that works to some extent, but I can’t help feeling that I’ve done something fundamentally wrong somewhere. Has anyone else got this channel working? If I was braver (and more competent) I’d call this out as a possible bug …

Thanks in advance