And I wonder if the game was designed purposefully so Germany can build PAR-1 at start and also that they represent 1939 circa as you stated. I mean, that seems like a very big nudge from the game designers to, "Please use them to help annex Poland."
In earlier versions(maybe including 1.08) germany only had blueprints. The change was done by so that german AI has less issues having enough Paras in time for the Norway campaign. For the poland campaign paras are of little help. They are more interesting for sea lion and gaining another angle of attack for huge battles. And huge battles means something bigger than the poland campaign.