I genuinely think that whatever that update is has something to do with the fact that they have not released full reviews yet. My suspicion is that there is something that they want to add or change or enhance on the performance version before they allow the YouTubers to fully review them.
I've thought this from the day they released it and no full reviews were available (still aren't). And as soon as rivet-gate happened on the CT, I thought... they probably don't want another release glitch like that. It must be something that's holding them up even if it's unlocking a little more power or something. It could even be something silly like a child seat latch position or something (as happened I think in Australia). Just dotting their i's and crossing their t's. They must be close given the EDDs we are getting.