Eviction of Elderly after 30 years for NO REASON OR FAULT

My grandparents have rented the same apartment for 30 years from the same landlord. My grandmother is now in a nursing home and it is just my grandfather still living there now. I do stay with him now though to care for him as he is 87 years old and has moderate dementia and needs the care. He is not at the nursing home stage and we want him to live as normal as possible for as long as possible. The rent is paid to date and always has been. The landlord and the family do not get along and have had issues as of late. Now after 30 years of being a tenant and having to place my grandmother in a nursing home, the landlord has served my grandfather with an eviction notice to vacate on or before the 30th of June. We really don't have the funds to move him anywhere, and we don't know if they ever paid a security deposit upon moving in. My grandfather has done nothing wrong and is a quiet and clean tenant. For years he did all the work around the house and yard for the landlord. They are a month to month tenant, but with really no fault of his and his age and medical condition is there anything that he can do to stop this or get more time. Please help, we are in a real bad bind here. Thank you to anyone who can help with answers.