New landlord advice needed

[Jordan Kim]

I am closing on a duplex next week and need to move in within 60 days due to the loan. The tenants lease goes through June 1st but to meet the 60 day term I offered them cash for keys to leave by May 1st and they signed a notice to vacate form. 

My question is if I end up needing to evict them, am I allowed to use the May 1st date as the end of their lease since I have a signed notice to vacate? Or if they go back on accepting that offer would I need to honor their June lease term? 

The tenants have only lived there since January and there were a ton of red flags and screening wasn’t done right. I have a feeling from conversations that they may not go easily and an eviction may be needed.

thanks for any insight!