As practice shows, not always partnumbers for A6/A7 begins from 4G.
I have now installed firmware "MHI2_ER_AU57x_K2519_2" MUVersion "0389" with number "4M0906961C"
Of course, I can return the sd card. It cost about 35 euros.
Unfortunately you can make a mistake like me. I was guided by this logic for my MIB2High on Audi A7, and ordered sd card with number "4M0906961N", where the letter "N" was the newest from available. However it was "Updatemedium" for the new Audi A4, A5 with SVM-Code: MI2HSEU129, and can not be ...