Concert Headunit

nope - unfortunately

Yes it does, all Audi head units have both front and rear pre-outs. The Bose programmed HU uses both of them to drive the Bose amps, and the non Bose just uses the rear pre-out for the rear speakers.
They are on a non standard mini-ISO plug, but an adapter is available to convert to standard RCA's with remote on lead. Some HU's have an integrated plug with the CD changer and DIS loom connected to the same plug, but most have a single multicoloured plug that can be separated and the adapter slotted in without any cutting needed.
You can also pick up the rear pre-outs and remote on from the rear amp bolted to the right rear speaker.

My mistake I was thinking about it with out making any alterations or using adaptors