Understanding Society User Support

Dear everyone

We are currently working on a project about EU Citizens voting rights in England on local level. 1996 was the first year EU Citizens were allowed to vote in English local election.
From UK Data Service we received the Conditional Access Dataset SN6027 with Local Authority Districts. The LAD Codes we received are the 9 digit ONS Codes implemented 2011.

Since we want to exploit differences in time of implementation between districts, we need to identify in what district a person lived before and after the implementation in 1996.
Using the 2011 9 digit Codes, we lose a lot of information, because a lot of restructuring happened and districts have been abolished and merged to larger units since 1996. (Looking back from today (9digit code), we don’t know anymore, in what exact district a person lived)

To be as precise as possible, we need the former 4 digit LAD Codes for every Person the year the Person joined the BHPS.

Is there any change you can provide this information to us? Or where do we have to ask for it?

Thank you very much
Kind regards
Matthias