Thank you so much, that exactly answers my question with the official response (that guy works at Meta) that confirms it's the same base model!
I was concerned primarily because in the release notes it strangely didn't mention it anywhere, and I thought it would have been important enough to mention.
Can SFT be used on partial generations? What I mean by a "steer" is a correction to only a portion, and not even the end, of model output.
For example, a "bad" partial output might be:
and the "steer" might be:
but the full response will eventually be:
The corrections don't include the full output.