Unregistered lease

I am acting for a client who is selling a flat. It has just come to everyone's attention that a lease extension created in 2021 was never registered. We are therefore trying to work out the best way forward. I understand the Land Registry has a registration period of 2 months after which it does not have to accept applications although in reality it often does. Are you able to indicate the likelihood of this lease been accepted for registration if the application to register were submitted now?

Laura - the 2 month thing is rarely an issue providing you lodge and explain why the delay