patch and target audio shortcuts

Yes there is.

First step: Set audio target to follow audio  source:

Second step: Set your source tracks for 1&2 > 1&2, define a source assignment preset, set them to 1&2 > 3&4 and define a second preset.

You will find these options in the context menues of the target and source track buttons.

Now you can switch easily by a keystroke between the options.

By the way: I still find it strange that in Premiere I define what will be cut onto and where in the timeline on the source side. The recorder side should be dominant like every tape machine or other NLE does.