Proper Notice for Lease Non Renewal

[Amber Forkey]

Location: UPSTATE NEW YORK

Hi all! First off, I'm not certain this is the appropriate forum to be posting this on so apologies ahead of time if this is not the correct space. 

Situation: House went under contract for sale with long term tenants who have resided in the unit for more than two years. Is it true that a month to month lease cannot terminate mid month? I'm aware that they need a 90 day notice but let's say that notice was given on March 11th for a non renewal of lease, would it be terminated on June 11th or would it have to go for the rest of the month? Their original lease began on the 1st of January 2020. 

Looking forward to the discussion.

~Amber F.