2015 A3 2.0TDI Sluggish?

Hello everyone!

Soooo, where do I start!

I've had my ECU Mapped (Dyno) By Darkside Developments about 4 months ago and they did an amazing job took their time with it (all day). For some stupid reason I decided to take the Audi and treat her to a service at an Official Audi Garage & also go roped into taking the service plan out which seamed like a fair deal at the time.

Knowing how Responsive/Snappy & Quick the car was before taking it into for its Oil change I left it in the safe professional hands of Audi, Had the full Audi cam review and everything was "Spot on" with the car.

So I picked the keys up and drove out of the dealership and let the engine & Oil heat up before blipping it up the slip road to join the motorway when I noticed that the Snappy, aggressive Torque pull has almost disappeared. I though nothing of it and just casually drove it down the motorway for another 10mins and tried her again but had the same results. I feel like the map is still Defiantly there and hasn't been erased as I can just feel the car trying to pull as hard as it used to.

I feel like its lost the throttle response, Pull and overall Performance by up to or as much as a 1/4 of how it originally was.

I've checked Oil level as they may have overfilled it but the levels were fine.
I've checked the "Drive mode" and that's correctly selected "Dynamic + Individual".
I also have V-Power Diesel in from shell so no S*** fuel is being pulled through.

Can anyone shed some light on this issue, maybe someone has had the same experience, maybe fresh oil does effect performance for the first couple hundred of miles E.C.T.
Also if anyone knows during an Oil change that Audi like to "Update the Engine Software" and could of potentially Erased the Map or if they do anything else during the Oil Service.

Thanks in advance for anyone taking their time out to read this post and all replies are greatly appreciated.

Ben.