Save up in the beginning of the game. Thats when you men can handle the enemy with out support and TP's come in faster , try and use as little as what you save as possible so if a blitz comes or a bomb takes out half you men you can reinforce.
I think you got it backwards , bunkers are the indestructible ones where you can't see what's going on outside, pillboxes Are the ones you put machine gunners in right?
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