Tenant lied on Pet Form with a breed we don’t permit, what now?

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So, our new tenant signed on for a year lease without a dog at first but with intention to get a dog. We informed them ahead of signing of the breeds we don’t allow. 
Our tenant finally got his new puppy which he is claiming is a Boxer and it is written on the adoption form but with the pictures they sent in, it is clearly a Pit Bull and we don’t allow it. I called the SPCA with the id number and adoption confirmation and found it is truly a Pit Bull. 
Where do I go from here? Give them a timely manner to get out 3-6 months (they have 10 months left on lease), evict right away, or let it stay until end of lease and not sign with them again?