Legal Question in Disability Law in Illinois

Yes, if it is a legitimate position elimination.

More importantly, however, is to look at whether or not you are on "job protected" leave. FMLA protects you for up to 12 weeks of leave if you qualify and if your employer is a covered employer. Once you exhaust FMLA, depending upon your medical impairment, you might qualify for additional leave under the ADA. But, in most circumstances, an open ended leave or leave of over 3 months in duration is not protected under the ADA.

It sounds like you have been off work almost 4 months. That is often a tipping point where employers either fire you or tell you your position has been eliminated. Hopefully, they offered you some sort of severance package.

Also, I am curious to know about your LTD. Typically, to qualify for LTD, you must show you are disabled and not able to work at all which is not compatible with protected leave. All in all, you should pay a qualified attorney to review your situation for your peace of mind. I am not able to solicit your directly online but can tell you I have handled many cases like yours.