Is this a Cunning Plan?

I own a leasehold flat on a long lease. I have rented to the same tenant for 17 years. She wants to either let two bedrooms or grant licenses to two individuals to occupy those bedrooms. She resides in the third bedroom. She manages the property. If the flat would otherwise be an HMO is she a resident landlord exempted from having to apply for a license because she only has 2 sharers?

Her own status is tenant under an AST currently holding over. If the answer to my question above is that I, as her Landlord would be required to apply for an HMO license, would the situation be different if I granted her a long -term AST, say 5 or even 10 years with a break clause?

The main question  we have is whether, if we give our tenant a rent to rent agreement, will this mean we can avoid having to apply for an HMO licence?! Or is there some other way that our long-standing tenant can continue to sublet to two other people without us needing to go to the expense and hassle of  HMO scenario?

Thanks

Juliet