[Mike]

Here it is from this lunchtime (grabbed off iPlayer, hence the BBC logo)…

That really is bizarre, it may not be as obvious but you can see when they're opted because the network picture quality decreases, and nowhere else seems to need these.

I wonder if it's as simple as a legacy thing that has not ever gone away (or kept locally because "that's what we've always done"?). Lots of strange things like this happen just because of corporate habit or local interpretations of things. It may be as you said, the complex nature of their opting arrangements - maybe it's a way of determining where they have opted out? Perhaps on their stack they have 'BBC1 LS OFF AIR' and 'BBC1 HU OFF AIR' to make sure things are working as intended and they aren't just going to hijack Hull's output inadvertently.

Are there any insiders that can explain it?