Unless the agreement is unlawful in some way, the courts are not going to void it. The landlord and tenant agreed to do something presumably lawful; so, the courts will reform the agreement to make it comply with the statutes.
The courts can decide to make the rental month-to-month or a one year rental. As between the two choices, the courts likely decide that the agreement is for a one year rental.
The difference between 12-month or 13-month likely has no practical effect unless the landlord or tenant is wanting to break the lease earlier than 12 months as both landlords and tenants dislike moving in and out of rentals and prefer the tenants to stay put as long as the tenants can. In this case, you do want to end the lease earlier.
My take is that the parties counted the dates wrong and did not realize that the dates as written would come out to be 13 months, instead of 12 months.
You can review your specific facts with your attorney to find out your legal options.
The lease is valid for one year, but no longer than that. After that the agreement becomes a month to month and can be ended with a 20-day notice to terminate the tenancy properly and timely served by one party on the other.
The lease would not be voided completely, the Court would, if asked, enforce it so much as possible, so for one year, then becoming a month to month. Typically if you have to leave before the lease term ends, you'd be responsible for an additional month because the landlord has a duty to mitigate his damages incurred by your breach.
This is not going to endear you to your landlord. The single best thing you can do to make it easier is to scrupulously clean the house so it looks perfect to make it easier for the landlord to get a new tenant. The other thing that sometimes helps is if you make an effort to find a suitable replacement tenant for yourself. Your landlord is under no obligation to agree to the potential tenant you might find, but if they do agree, then you have helped them and not left them in the lurch.
Hope this helps. Elizabeth Powell
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