Problem with units' buildup

[stelel]

Hello,

If anyone could help...
I am desesperately trying to turn my Soviet infantry brigades into rifle divisions - through the breakdown-buildup button or by pressing "b" - but nothing happens. My game reached november 1941, so I should be able to do it... shouldn't I?

[Helpless]

There was a rule change since release. Brigades can get combined starting from May/1942.

[stelel]

Hummm... thanks very much!
I was guessing something like that...