hey everyone, my first time on here as figured id ask the question people in the know!

im currently awaiting delivery of my new A6 Avant Black Edition (2.0 TDI) and have been looking at various styling kits to give it an extra "edge". ive been looking around the web for a rear valance / diffuser which looks similar to the RS6 styling, whilst I know that the entire bumper (front and back) are different, I know that you can something similar, from maxton.

what I cant figure out is that most "kit" providers only mention the C7 A6's are from 2011+ but tend to stop the date refernces at 2015 - and even then, specify that they wont fit the S-line models etc.

am I right in presuming that the Black Edition is essentially an S-Line body style, but with black trim?
Also, the 2017 rear end has square exhaust outlets, vs previous styles having circular, is this just an internal styling difference, but the out profile being the same as it always has been from 2011?

has anyone had any experience in fitting these things? on this type of car?

im looking at :
CSR - Audi A6 C7 S-Line 11- ABS Plastic Rear Bumper Diffuser | Mad Motors

Rear Diffuser RS6 Style for Audi A6 C7 4G with Exhaust Pipes Tips 2012-2015 | eBay

Again - looking at the front end:

FRONT SPLITTER AUDI A6 C7 S-LINE v.2 - A6 C7 - AUDI - BODY KITS - MaxtonDesign.co.uk - ONLINE STORE
says from 2011 - 2014 - so how different is the front / rear on the 2017 models if they are all classed as C7's?

im not looking to modify any of the elements of the bumper, or part, just a straight swap out.
if you have any other links, or suggestions, let me know

id appreciate your thoughts and help on this
cheers