Shared Address Import Problem (Master Address ID)

[gibsonoliver]

Hi

On our main CiviCRM site we have started using the new 'Shared Address' function.
As we have 11,000 contacts on the system it makes sense for me to export the current employer (ind to org) relationships and other fields, identify which individuals have the same address as their employer and then reimport the individuals specifying the shared address.

I've started the import process (update) using a CSV file with;
- Individual's Internal ID
- Master Address ID (to Main Address)

I thought that this would then overwrite an individuals Main address with a shared address (the employers) using the Master Address ID specified. The data imports ok but nothing at all changes.

Am I missing something?

Olly