Registration of new lease via expedited process

I am buying a property and the only thing left before completion can happen is registration of the new lease - it should have been done through the expedited process but it still hasn't been registered. How long is this likely to take? The property is Flat 1, 40 Manor Avenue, SE4 1PD 

Emma - we don't have an application to register a new lease re Flat 1. Can you check with the conveyancer to confirm the title number/our case reference please? If they can confirm those two details I can check again for you - TGL553419