Well then prepare to be shocked.
With Blago's rape and pillage of the IDNR's funds during his reign of terror the IDNR most certainly didn't have the funds for a relocation program for Bobcats. Quinn didn't help matters much either. But nope there was no relocation/repopulation of the Bobcat in Illinois. They did it all by themselves (well with the help of being on the protected species list) the old fashioned way. You are probably seeing the results of good cover and habitat growth spurring on reproduction. More kitts surviving. I would assume where you are seeing them has a pretty close habitat to the way ours is. Good young tree growth, lots of underbrush, plenty of mice, rabbits, and squirrels to munch on.