Generally it is true that at the expiration of the terms of a written lease, a lease converts to a month-to-month tenancy. If the landlord resorts to legal action, and the landlord is subject to the Chicago ordinance (RLTO) then this may be some leverage in a counterclaim for the action. There is always some risk in going to court, so if a compromise could be arrived at, both sides would benefit.
There are a number of resources for tenant's rights...
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