Amir from Nottingham University has shared some documentation to import and export the items for the DSpace repository.
Basically the preliminary plan is to try testing a bulk import on Mimas front, and then get the items from Nottingham. There is a need to understand this export/import mechanism well which is not documented very well.
Once we get a database dump, we will try to setup a mechanism to be in sync with any data updates/uploads so that both Nottingham and Mimas DSpace sites are mirroring each other.
Watch this space for more about the data migration.