From all the testing sites & schedules I just googled in IL, it appears that April 30 was the end of testing. Though, perhaps IDOA @ Springfield will administer a "walk-in". It's worth a call.

But, are you sure you need a license for at least this season? They are only required for "Restricted Use Products" (aka RUP). Atrazine would be restricted use. Glyphosate would not. Liberty would not. Enlist would not.

Just search for a label of products you intend to use and look for the words "Restricted Use Product" on the label front page. Atrazine or Atz containing products are always RUP.

I'm not anti-license advocating, but I think you may be in a bind for testing this season. I got my first commercial applicator permit in 1974.