If you buy a title plan or title register document you may see an error message about "pending first registration".
This basically means that someone has registered the land at the Land Registry and that process is still taking place. It typically takes 3 to 4 months to register land, so you won't be able to see who owns that land until the registration process is complete.
Why can I see the ownership boundaries if the land is not registered?
The Land Registry immediately adds the ownership boundaries when they receive an application to register land.