The change to the vacuum actuated system was start of Nov '08. So if your month/year on your door sticker (door or door jamb) is 10 08 or earlier, you'll have the electrical system.

The bigger change about the move from the electrical to the vacuum is the separation of the flaps from the supercharger.

Here is the through Oct '08 look - https://audi.7zap.com/en/usa/audi+a5.../1/133-133082/
25 is the motor and 23 are the angle sensors

Here is the since Nov '08 look - https://audi.7zap.com/en/usa/audi+a5.../1/133-133083/
a much cleaner supercharger config, and
https://audi.7zap.com/en/usa/audi+a5.../1/133-133085/
showing the new lower manifolds and the vacuum actuation

I recall some time back some thread on the pre-Nov08 style here or at AW where one of the flap blades became dislodged and blocked movement of the runner. Being all integrated, not sure how he eventually resolved the issue.