Facebook almost always has a long-term holdout group in experiments like this to make sure that any gains from the design change aren't just short-lived blips from the novelty factor that ultimately result in long-term regressions.

I understand but, they announced that it would disappear in September. We are at the end of October. Considering the feedback, I'm quite happy to be still on the old version.

They are probably rethinking now after seeing the feedback

Yeah. Like they re-thought the wall or feed or messenger as a separate app. All of which got negative feedback.