Armies of the Stalingrad Front (61., 62. & 63.)

[PreußensGlanz]

Hi
I'm interested in the deployment of the armies of the Stalingrad Front that defended inside the Don arc, these are the 61., 62. & 63. Reserve Armies.
What I would like to know is, did they form a defense line or were they advancing to meet the Germans?
If they formed a defense line, when was it established and where was it?