In the past, the Secretary of State did not follow the rules for issuing the EL series of plates. Here are the samples of the Electric Vehicle and Restricted Electric Vehicle plates.
The 2002-2003 license plate guideline said:
Electric Vehicle license plates are issued for any First Division vehicle propelled by an electric engine without using motor fuel and having a maximum speed of less than 45 mph. Electric vehicles designed to travel 45 mph or more have an “A” prefix on the plate (625 ILCS 5/3-805).However they commonly issued the A plates to vehicles capable of less than 45 MPH, and the 'non A' plates to vehicles capable of more than 45 mph. (The reverse of what the guideline suggests)
That plate guideline is currently at:
www.sos.state.il.us/publications/pdf_publications/0203lp_guide.pdf but I have a downloaded copy if anyone needs.
More recently, the requirement that the Secretary of State issue distinctive license plates for electric vehicles has been deleted from the law. It was unclear how they were going to implement this, and it appears they have not implemented the over/under 45 correctly. There is an affidavit available from the Secretary of State to certify that an EV is capable of more or less than 45 MPH.
Perhaps, in the past, they issued the incorrect series of plates, and are treating the renewals based on the faulty information.