Apparently don't understand research

Was trying to get groups of archers. So I researched warefare up to get to advanced archery and I made it (w00t).  BUT when I go back to research warfare again, logistics isn't there (which makes it possible to make groups of 3 and more). 

I understand that everytime you research one of the 5 main research groups it gets harder, but I didn't know you loose a chance to get technology.

Is this intended?  If you go past a few research levels do you miss your chance?