Face lifted versions of various Audis including the A6, A6 Avant and RS6 Avant were seen testing in winter conditions together recently.
It looks like all of the A6 range will be in for changes based on what was seen but probably only small changes. The exterior changes, particular will be very minimal as would be expected from Audi. Inside there is likely to be some technical improvements but possibly not much else changing there.
It is expected that the engine will be the same as the current model with all the options including the 190 hp 2.0 litre 4 cylinder which is very frugal and managed 61.4mpg UK. It is expected that this new line up of face lifted A6 cars will come out towards the end of the year.