You can always sue to recover your deposit if you have good facts. Here, there is a written agreement, and you cannot contradict a written agreement with evidence of a subsequent oral modification. When you moved out and they concurred that you had a six month extension, not an additional year's lease, that should have been the end of it.
Landlords always have a duty to mitigate their damages when a tenant leaves. If the tenant leaves early, the MOST a Court is likely to order is ONE additional month's rent, not an additional six months, no matter what the landlord thinks.
If they failed to account for your deposit, read the deposit statutes carefully and decide if you have a good basis to go after them for TWICE your deposit. Elizabeth Powell
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