

I think the leaked US plan is real, and Russia is playing along for now.
In my opinion, they are giving Ukraine (and Europe) a final chance for a reasonable deal. If they reject, Russia will lock in and fight for total victory, and the US may stop sending weapons.
Russia will demand at least partial demilitarization of Ukraine and/or withdrawal of their military from the land east of the Dnieper river. It would be a tough pill for Ukraine to swallow, but it’s not impossible that they accept.