Actually, as the germans I would never try and advance to Saratov. You have to conserve the Axis strength. They only get 300 infantry a turn. I found that when I reach September, I only fight in limited areas. In October, I only fight in one area...until finally, I can't fight no more, as my divisions are all getting too beat up.
One very effective tactic that my opponent likes to do is to group all his tank brigades into one tank army with a good leader, then throw them at an infantry line. They cause a lot of damage. (like 1200 men lost per battle.) And while they are very easy for me to counterattack...it sets up a chain reaction where my units that counterattacked have loss readiness, and can in turn be reattacked. They can also be railed around easily.
And the Russians can afford the tank losses. I can't afford the infantry.
Unless the game ends in an automatic surrender, (and that means Uralsk or Baku) you are going to be playing until spring 1943. At some point you are going to collapse as the Axis.
“My logisticians are a humorless lot … they know if my campaign fails, they are the first ones I will slay.” – Alexander the Great