As others have said it is just undoing what was done 2-3 years ago. In that time Newsnight has actually quietly been cut from 50 to 40 minutes a night - it's now scheduled to finish at 11.10 with the weather getting a 5 minute slot in the EPG
I don't expect anyone here to agree with me at all, but...
I would advocate Newsnight becoming a 30-minute* programme five nights a week (*well, strictly speaking, about 28-minutes to allow for weather/trailers afterwards) starting at either precisely 22:30 or precisely 23:00, simulcast on BBC Two and the NC.
There may then be the odd rare occasion when it goes out on the NC only, if BBC Two is showing some live evening event/sport (either always planned that way, or dropped on-the-fly if the event overruns). In the case of an unplanned overrun that only partially eats into the should've-been-Newsnight slot, BBC Two could either milk the post-event waffle/punditry accordingly, or show some short-form filler programme.
Just an idea.
I could charm the vultures off a corpse.
Ne1L C and watchingtv gave kudos