The White Autumn scenario is not new, but there should be new features in:
Example sometime the Eastern can control many Petliourists units (not those created by the AI before) if Western ally with them. Those ukranians are sort of 'western whites' yes, but you don't controle the whole Western White.
I think I can quote from the beta, it must not have changed:
andatiep wrote: you can play Ukrainian Nationalists now with Davaï. You can do it as an Eastern white player, ...if the Western White player succeed to activate the Option "Battle of the Chiefs" which allow the alliance between Ukrainian Nationalists and Russian Whites. And even if you don't succeed to activate this Option, you will be able to play them together with the Poles, as soon as Poland attacks in early 1920.
ERISS wrote:It should be for misplaced pride and divergency of strategies or interests, bringing some mess in military orders and perfect coordination between Petliura and Denikin..
andatiep wrote:- Ukrainian Nationalists, even allied with Russian Whites would really watch for their independence and probably would avoid to be commanded by Russian leaders and merged in Russian divisions and corps. The same for the Baltic states but we can't to it for them so easy because of the Pskov corps needs.
- Like with Poland managed by the Eastern Whites, it was to give something to manage to them for the late years of the RCW if, like in the history, they would have few things left to manage after its deafeats in Siberia, as soon as mid 1919... But finally, i didn't see a RUS game where the Eastern Whites are defeated as early as IRL

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- With Poland managed by the Eastern Whites, it was easy to merge like IRL the Ukrainian Nationalists and Polish troops after they allied together, just before Poland attacked.