Tenancy over, but a sublet-ee claims she has right to stay on

A situation where there was a tenancy in place since circa 2015, the last named tenant on the lease has moved out, and tenancy officially ended last week. One of the girls has stayed on, she was never on the lease, just a friend of the named tenant and 4 of them split the rent.
1. She is there several years, what might she be entitled too in terms of notice?
2. Also a worry is the insurance and being able to get work done inside the house if she digs her heels in and won't leave,
and
3. Can she move in her partner without permission? landlord has a sense he is already in.
All professionals.
Edited: The head tenant gave notice of quitting, to the homeowner. The sub-tenant got in contact with them to rent the property, however the agent served a month's notice, House is 20-plus years old and needs a complete overhaul. Owner would prefer they moved out.

Was the landlord aware of or did they agree to the sublet. If not this person is just a licensee if not a trespasser. Throw them out and change the locks.

@cremeegg Landlord and management agent was aware. No written consent. Different ballgame then?

Lone Star said:

@cremeegg Landlord and management agent was aware. No written consent. Different ballgame then?

Click to expand...

I don't know. Probably.

Multiple Occupants

A person cannot assign or sub-let part of a dwelling and this may cause difficulties in shared accommodation where there are multiple tenants and some wish to leave but some wish to remain. In this scenario you cannot assign or sub-let individually.

It is possible for multiple occupants to bring in a person as a licensee however you need to ensure that in doing so it does not lead to overcrowding and they have an obligation to inform the landlord of the persons identity. A licensee does not have the rights of a tenant but after 6 months occupancy they can apply to the landlord to become a tenant and join on to the existing tenancy. This should be acknowledged in writing. If the request is refused a licensee can refer a dispute in these circumstances to the RTB.

hmmmm...the person staying on might be a licencee....can teh landlord offer the person a 6 month lease? and is that person entitled to move in a third party?