As of October 1, 2020, there is a new Federal income withholding for support form. This was done on short notice.
For the current Federal form, click here: https://www.acf.hhs.gov/css/resource/income-withholding-for-support-form
I have updated the previous version of the Illinois form that melds the State specific requirements with the Federal form.
Feel free to give me a call if you wish to receive a fillable copy of one that conforms to the Federal and State requiremetns.