Bumping schema version causes duplicate credentials to be generated

[esune]

When bumping the schema version for a registration credential (e.g.: registration.registries.ca in OrgBook BC), issuing a new credential for a legal entity that was already registered (e.g.: the topic was already created) results in two almost identical credentials, exception made for the version of the schema used, to be attached to the same topic.

Is this behaviour expected? I was expecting the new credential to supersede the one already issued with a lower schema number.