Thanks a lot Andy - I hadn't known about this. I've just signed up the trial (though I don't have a current pass). I guess I'll hear from them about the trial and get a pass once I do if looks promising.
Thanks again for letting me know.
@Polo1 the trial had not ended. More content will be released in due course. It will be the responsibility of the providers of non Sky owned channels to provide subtitles.
Here i s the current Subtitles listings on the Black Box and MSartbox.