I was told that one can file a complaint retroactively.  Even against retired officers.  Is this correct?

Source of information?

Well I do not know if the source was correct.  That is why I asked.  After what they did to FFLS in the state, I will believe about anything.  I am still unclear about what they did with Qualified Immunity.  I was hoping somebody who understood these things would educate me.  I have asked an attorney and a retired LEO and they have not answered.

Either the new rules about filing a complaint go into effect retroactively, or they go into effect as of a certain date.

Public Act signed by the Gov

https://www.ilga.gov/legislation/publicacts/fulltext.asp?Name=101-0652


Abolishing cash bail was reported with an effective date of Jan 1, 2023.

The signed bill becoming Public Act is reported effective July 1, 2021.
https://www.ilga.gov/legislation/billstatus.asp?DocNum=3653&GAID=15&GA=101&DocTypeID=HB&LegID=120371&SessionID=108&SpecSess=

I dont think all sections have the same date.

It's a 700+ page bill that was just signed into law.  I think you might be asking just a little much.  If you aren't willing to read 700 pages and find out why would they?

Well, because so far I have been unable to find the full 700 pages.  And you are right, I am unwilling to read the darn thing for one simple question.