Now that the 7th Guards Army have deployed in-force, the 56th and 3rd Guards armies can truly retire to the rear for a few turns. Rostov is being squeezed, but I'm confident it can hold for at least another two or three turns/weeks. The German XXIX Korp has crossed the river to support the III and I SS Panzer korps, while the 16 Panzer Division presses toward the river crossing northeast of the main battle areas. However, the 1st Guards Army is deploying just in time to keep the Germans at bay for at least some time.
The 62nd and 63rd Armies will need some help soon. But I'm not sure where it will come from.
Defending the Caucasus will depend greatly on how hard the Axis push their offensive into the region. If the pressure keeps up, the Russians will likely have to give up Rostov and retreat to the south and east, protecting Stalingrad as the main objective. I don't envision any major offensives/counter-offensives on the Eastern Front until 1943.