Glad to hear issue resolved ...

The tiptronic transmission you have is the same being discussed here Link:- ZF 6HP19A tiptronic gearbox (A6 3.0 TDI Quattro)

There is also a version of the TPI / TSB being discussed in linked thread for the Phaeton ... possible related thread Link:- VWVortex.com - Phaeton ATF Concern (Please Help!)