Currently users are managed per instance (dev/release/master) and per country. The idea is to have* one overview where you can create a user and simply select which instances the user should have access to.*
In addition to that: For NROs covering multiple countries, it would be handy to be able to manage all the users - from all the countries, and all of their instances - in one go.
This could be a feature accessibly to only 'super admins', on the master instance, from where the changes are pushed further.