Paul's posting above has triggered a question in my mind.
Valjoux.92 movements with 30 Minute chronographs instead of 45 Minute recorders, how late & how often do we see the 30 Minute version offered in the Carrera range.
It has been my observation that the rarer 30 Minute version are mostly observed in the very early Dauphine series of Autavia's. After this period (assume 1963 & onwards) the 45 Minute version of the Valjoux.92 are far more common.
It may even be that others disagree , i would like to hear your thoughts/observations on this point.

Follow up point to the above
Due to the fact the timer from the eBay auction has the 30 Minute register i would have assumed it was powered by a 77xx series movement.
Again I'm open to hear others point of view on this theory.

Cheers - Darren