Property Subject to tenancy

[Mark Reit]

I hope to be closing a a rental property next week.

The contract signed a few months ago is "subject to existing tenacy."

The lease is only until the end of January. My question is, if the seller decides to give a new lease to the current tenant for another 12 months without telling me, would that be allowed? If the contract is subject to "existing tenancy", does that mean I accept the tenancy at the time of the contract or any existing new tenancy?

Thanks,