That sounds like heavy losses on their parts. I'm thinking of the beginning of WWII when the Japanese eventually lost so much of their best pilots that their training kept getting shorter and shorter until their pilots were about useless. Which in turn, resulted in the introduction of the Kamikaze pilots. So, as the hardcore insurgent replacements become less trained and less effective they will step up suicidal attacks and so forth to make up for the shortfall out of even more desperation. That is if we keep up the current pressure or even increase it.