Hi Ryan - an application to transfer part (split) of the title you refer to was submitted in December. The Transfer completed in October. It's currently waiting to be processed. The provisional new title for the transferred part (13) is BD360279
13A will be the address for the retained part it seems
If you are buying 13A then the conveyancer should request expedition of the pending application to hasten the process -
Request an expedite - GOV.UK
I'd recommend speaking to your conveyancer/the seller to arrange