Software vendors received the below message from the Illinois Department of Revenue.
“The Illinois Department of Revenue will be implementing a new version of its tax system over the Labor Day weekend. The update is a major version change and will require the BIT and IIT Modernized e-File acknowledgement process to be shut down starting Friday, September 3rd, 2021 at 4:00pm and will not begin acknowledging the submissions until Tuesday, September 7th, at 9:00am. You will still be able to submit Illinois business and individual income tax returns during the version update but no acknowledgements will be generated. Please remember to reach out to any clients that file during this period of time and communicate that they will not receive an acknowledgment until September 7th.”