If an apartment you rented is not available for occupancy at the beginning of the lease term, you have an opportunity to rescind the lease if you've had a change of heart after signing it. For example, if the apartment isn't ready when it's supposed to be, it can be a way out.
Another opportunity arises if at any point your apartment becomes uninhabitable, due to destruction or decay of the premises or a lack of maintenance. You then have an argument that because the landlord has not upheld his or her side of the bargain, you should have the right to surrender the unit and be free of any further lease obligations.
Landlords often oppose these arguments. Sometimes they cite to a provision in the lease saying tenants do not have the right to cancel it under these circumstances. Even if a written agreement prohibits surrender under particular circumstances, the lease provisions may not apply, or they may be unenforceable, so it still might be possible to withdraw from it.
It may be that your right to rescind the lease will look so strong that the landlord will just go along with it and let you out. Or perhaps you will need to do further negotiating. In some instances, you might need to have a court order it when you bring or defend a law suit.
Under standard contract theories the judge may release you from the lease. The court may also determine that provisions saying you can't be released don't apply or are unconscionable, and therefore unenforceable.
Although laws require leases to be written in understandable language and not indecipherable legalese, they are legal contracts. Interpretation of lease language is best left to a lawyer who practices Landlord Tenant law. Let an attorney review your lease and the facts to determine the extent, if any, of your obligations and liability.