@MIT_S60 I am not sure if this is entirely correct. My S75 RWD has DU00 or new drive unit but apparently the issue is not only drive unit and there are other components that need to be upgraded in order to uncork the car. Moreover, I see all inventory RWD models are showing 5.8 s now on Tesla website even those made after July. The same for S75D models that is showing at 5.3 S even though based on your claims those S75D should already have the capability to be software upgraded.
I am having lots of discussions with Tesla currently for this issue. Before I bought the car the salesperson explicitly confirmed the car would have and will be eligible for upgrade and my car would have the 4.3 s performance.
Before delivery of the car, I contacted service centre and they also told me the car will have latest update before delivery (not sure if they did understand my question and gave an unthought answer).
After delivery, I noticed the car was not as quick so I contacted the centre again with my VIN number and they confirmed my car had new drive unit and its acceleration was 4.3 S.
Then I got the Power Tool app and tested the car and best I could get was 5.6 s.
@Krash kindly helped me to analyse the data and ideed the car was slower.
Then I raised the issue again with Tesla and this time they said it was a mistake and my car could not have the performance upgrade or be uncorked. I am currently having a serious discussion about this with them as I feel Tesla misrepresented their product to me in several occasions. I am not suggesting this was deliberate to get rid of RWD inventories or to boost end of quarter sale but whatever happened the result is that I was sold something that was not as offered to me.
I think I gave this example somewhere else in this forum. Imagine you buy a TV with 3D capability only to realise it can not play 3D movies when you bring it home then you go to the shop and they say oh..yes, it was a mistake but don't worry at least you have a good TV!
Cheers