I'd be surprised to see WB that soon, though a box with PanO/Sval and YJ/WB would be excellent thematically.
Considering that all of WB's flagship units (Daofei, Guilang, and Tigers) all tend to operate independently and are fundamentally against Fireteam eligibility, I'm hoping we see a sectorial designed less around fueling janky fireteam compositions and more around empowering those flagship troopers, or giving them unique profiles. It might be because I'm a far better player when it comes to breaking fireteams than when it comes to actually playing them, but I wouldn't mind diversifying sectorials to be more than just a vehicle for link teams. JSA is a great example in that regard. For the problems it does have (which stem more from aging poorly with the current shift in CB's design), it packs a lot of unconventional options into a sectorial and isn't dependent on its fireteams to exist.
All I want from White Banner is the Blue Wolf. And I want it to be something greater than, "It's a Guija but we painted it blue lol". I want something with tricks up it's sleeve dammit.
The Yu Jing occupants of Svalerheima, they seem to follow a more sneaky camo centric playstyle playstyle and is rumored to possibly include units like the Zhanshi, Tiger Soldier, Daofei, Shaolin Monks, and Guilang. Hac Tao have been mentioned as well but nothing is confirmed for sure. We were told Tiger Soldiers were in IA, even labelling dossiers and announcing it as so, until they weren't.
They are the Yu Jing forces on Huang Di (Svarlarheima) They have fought PanO many times on the frozen world. It was a world initially discovered by PanO but Yu Jing set down and said "we are here, try to get rid of us." It makes sense why YJ did it too. It's a world rich in resources but especially Teseum. It's a frozen world with areas on the equator being the survivable area. It's thought that two things would effect the YJ forces there, the cold terrain and PanO. Though ISS is probably prevalent in the settlements. It may be the opposite of IA and rely a lot more on light troops rather than HI. But they will be there. We believe the force will have Daofei, Guilang, Tiger Soldiers, Shaolin. Mostly due to the fact they are not elsewhere. Of PanO I think it's only the Nisse and Jotum that are not already in a sectoral. I believe there's a knight order that has a monastery on on the planet. Existing troops I think/hope will be in the are: Su Jian (I think because of the multi-terrain, and I like it), Zhanshi. I'm also hoping they will split the Tigers Soldiers between those with Combat Jump, and those with Multi-terrain. And then allow the MT ones to form a fireteam. No matter what though, they are going to need to come up with all new troops to do it unless they want a mix of ISS and IA troops in there. Way back when, there was talk about it's own TAG called the Blue Wolves. Small TAGs that hunted in packs. Though it's thought it might be a TAG with Holo 2, and gives the impression of a pack. I really hope YJ gets it though. I haven't played Vanilla in a while so I can't tell what they need after loosing so much after uprising.
The Daofei was also listed explicitly as being a member of the Invincible Army in its fluff since the game's inception. This part about it being in the IA is even included in the N3 rulebook, so the retcon is extremely recent.
I don't think vanilla needs much due to Uprising, but they do need to stop being intentionally terrible at hacking. It's like Yu Jing just gave up on it and Yanjing never happened. They are at a base level of hacking when everyone else is engaging in an arms race (and Ariadna are the only ones smart enough to realise that not carrying nukes makes you immune to them... no wait... bad analogy) So repeaters, pitchers and some damned BTS on their KHDs.
As mentioned, it's the YJ Army on the Huangdi Peninsula of Svalarheima. It's also a Banner Army, so we should be seeing a lot more of the classic units: Zanshi, Tigers, Daofei, Guilang, Guijia (and/or a different TAG, as the old Jotum fluff mentioned a 'Blue Wolf' TAG that fought against Jotums and you could hear the clashes echo through the mountains). Fewer HI, more light troops.
White Banner does sound appealing. It would be really cool to have the "blue wolf "(pack?) if it was a a fun worthwhile unit to field. I love the idea of having a midfield skirmisher style of game play for Yu Jing. I think it would be interesting to have a new Uber Monk unit for flavor. I'm not sure what Yu Jing is still missing from Uprising. That would be a good time to finish filling that gap if there is one. Along with what @Mahtamori said. I would like to see some good doctor/engineer specialists with multi-terrain and good gear/skills. Also, perhaps, a new bad ass Yu Jing only REM with Multi-Terrain and/or Climbing Plus. We have room for a different TO Infiltrator too.
Let's not beat around the bush. Oniwaban. The Oniwaban was the biggest pain YJ suffered in the split, and nothing has done a very good job replacing it. Fortunately, WB is the YJ sectiorial that would have the easiest time fitting in a thematically appropriate solution. I also wouldn't mind getting some sort of biker unit. But that's a far cry away from the gap left from losing the Oniwaban. Regardless of what we end up getting in WB, I want it to stay distinctively with YJ. You don't see NA2 armies running around with linked Kamau snipers.
I think we'll see Zuyong like we see ORCs in Varuna and Neoterra. I think Mowang too. Maybe their only big heavy hitter. Mimetisim and multi-terrain makes them "in theme".