Buying a house this month, take possession next year??

[Daniel Kong]

I'm attempting to purchase a property with a tenant already in place. The plan is to purchase the property this month. However, the purchase agreement that my agent wrote up has "The possession of the Property shall be delivered to the Buyer on or before 1/31/2020". She said this is standard language in the purchase agreement when there is a lease already in place. I plan to honor the lease, but would like the lease transfered over to me, along with the security deposit and any contract with the Property Management Company. Does this verbage sound correct, or should it be worded differently? Trying to protect myself also against the seller extending the lease or changing the terms such as the monthly amount, etc. Thanks in advance!!