Switching a single tenant for another in 3 bed

There are 3 of us living in a 3 bed property with two guarantors (1 for 1 person, and 1 that covers 2).
1 tenant wants to move out and take out their single guarantor from the contract too. We’ve found someone to move in and have a quick switch over.

Our landlord is saying if we want 1 person to move and receive their deposit, we would all have to vacate the property, move all our stuff to return the property back to its original condition, and then move back in again with a new contract. Which seems ridiculous?

I’ve lived in places where this hasn’t happened before. How do we negotiate this?

He can do a deed of surrender

He is being over-cautious. There is no need to actually move out. You just all sign a deed of surrender when the person is leaving and then the new group immediately signs a new agreement. It does mean everyone plus a witness being present together at that one moment, but that’s the only way to do in a legally binding way, unless you all go down the route of a deed of assignment.