I'm saying that the gains were not a result of 1 week of post-training 6.0 Sol.

It seems that 6.1 Sol is closely related to Astra. As for whatever 6.0 Sol was, it's anyone's guess. I'd speculate that 6.0 was just 5.6 with post training. It's possible however that it is the same model but with severe performance issues resolved so they bumped the version number.