I've asked TAG Heuer the question- they tell me that there is a competition running at the moment, and so to be fair to everyone, they'll answer the question after the competition is finished.
I can't remember the conversation but I think I was told the assembly line production time is around 4 weeks.
I'll have to go check my notes to what I scribbled down so don't quote me on that...... yet....
I spoke with one of their watchmakers about servicing time too but i really can't remember any of the numbers given for that one as alcohol was involved during the evening.