That set was very close to N9 if I recall? It was sometimes used overnights in the early days of News 24.
I think you might be getting slightly confused there. In 1997 News 24 launched in N9 and did its own thing initially. The set seen in James's video didn't exist then. BBC World was its own separate 24-hour a day operation broadcasting out of N1. They used to use a newsroom background for bulletins but it was most definitely N1. I think this might be what you are thinking about overnight in the early days of News 24 as they used to dip in and out of World for a short bulletin:
https://www.youtube.com/watch?v=snYYL5CE-dg
From some time in, I think, early 1998 the joint overnight service launched between World and News 24 with N9 (News 24) being used most often.
Then, in autumn 1998 News 24 moved into the set depicted in the video posted by James - N8. News 24 remained in N8 until it moved to N6 in 2008. That original N8 set was used 24-hours a day on News 24 including the overnight joint service. World then moved into N9 later in the autumn of 1998 and stayed there until they moved into N8 in 2008.
Overnights definitely came from that unknown set for a period of time, or at least sometimes, as shown in this clip (skip to 46 seconds in).
Samira's sitting where Gavin is in the video originally linked.
https://www.youtube.com/watch?v=xY9aOVVSy9U
Yes, that's right -
N8 only opened for the first time in autumn 1998 and became the standard News 24 set 24 hours a day (replacing N9 which World moved into). It was indeed used for the overnight simulcast with World but once it opened it was
the
News 24 set - so it was used all day. Sorry, the way you phrased it confused me.
Incidentally that first set in N8 (and News 24's second since it launched the year before) was affectionately known as the "car crash in a shower" set if I recall correctly.
I remember that weekend - autumn 2001 if I recall correctly. In fact, I recorded that clip and it's obviously been ripped off for YouTube

Anyway, it was a maintenance weekend and I think there were some joint bulletins with World. On the hours where World only had a short summary they did that from elsewhere (probably a CSO set up, maybe in
N6?) and News 24 could use its own branding in N9. Maxine is sat in the usual World newsreader's position on the main N9 set there but for some reason they varied the camera angle on the News 24-only hours. The World simulcast hours looked a bit more standard and used the overnight vamp and generic titles.