I started the grand campaign, plsying the german.
I changed the settings a bit and raised the max. time to 90min because i was still learning the controls and playing around a bit. I never needed that much time but didn't thought about it anymore...

Now the russians started their counterattack, i hold the line thanks to the 8,8 but i can't attack myself because the Panzer III and IV stand no chance against the KV and T34. After i killed a number of enemy tanks they dig in themselves and we have a patt..but..what now...the timer shows 75min left^^

I did not found any way to change the settings while in the battle or even while in the campaign.
Do i have to wait for the time to run out? What happens if i accept the truce? I am supposed to defend and buy time so i shouldn't loose?

Thanks for your fast anwser.
I did not fought a Tankbattle because..well Pz. III J Command or even worse early support Pz. IV againat KV and T34...
I used digged in or hidden Inf. on the frontline and 3 hidden 88 as longrange AT-weapon.

But it's not longer important because i tried to win it after destroying 3 T34, 1 KV and 2 recon Inf while defending, well i won but because of this i losed the campaign. I did not know that you can win a operation at the first map.

Know i'm thrown in the next operation...i loosed one command Tank at moscow i could not replace and while holding off the counteroffensive one 88 got damaged, i lost one engisquad and another lost half of his members..not to talk about 2 empty slots because the points i got at the beginning at the counteroffensive where not enough to buy something really usefull.Weaker, stronger enemy and getting even less points...i would need 5 days without looses only to replace the missing/damaged/dead.

Seems your supposed to play the operation in the historic way if you want to play the campaign.

Edit:
And there is no way to change the settings after the campaign/a operation is started.