[JMT1985]

I've previously posted suggesting that maybe they'd opt for a structure along the lines of...
- 10.00 to 10.30: National & International news (BBC One & News channel)
- 10.30 to 10.45: Nations & English regions opt-out (BBC One), Sports bulletin (News channel)
- 10.45 to 11.00: Special/investigative reports (BBC One England & News channel), Extended nations opt-out (BBC One Scotland/Wales/NI)

This would avoid the regional news from being pushed back too far.  The structure could also be followed if the One gets extended to an hour. It also minimises the loss of News Channel UK opt-outs.  If the One gets extended in a similar way then I suspect the amount of UK opt-out gained would more than cover the loss of Newsnight being simulcast.

It would also potentially give the nations an extended bulletin, allowing for politics affecting the nations to be better covered along with more local news.  This concession could be particularly useful politically, should they ever need to close BBC Scotland channel for cost-saving reasons (reinstating BBC Two Scotland at the same time).

If BBC One did chose to opt for a one hour of news at 10pm the only show which I see affected could be Graham Norton's show on a Friday which has been pushed to a slightly later slot of 10.40pm now already - Graham would be moved to 11pm and probably his audience would be reduced even further.