Dear Patty, dear group:
I want to bring this to your attention:

Julian Ladisch, a core team developer, followed the discussion of the data migration subgroup on March 25 and this is want he wants to make the group aware of:
The functionalities which have been described by Wayne on March 25, 2019 (in the DM meeting) (Bulk-Download, Streaming, Bulk-Upload) have all been implemented in the Raml-Module-Builder (RMB) : ,
These can be made use of with very little effort (Streaming, Bulk Download) and little effort (Bulk Upload), respectively, in the respective modules. To accomplish this, it only needs adequate Tickets for specific (!) APIs. These Tickets can be implemented promptly upon adequate priorisation by the PO. (E.g., has not been prioritized highly since two years ago).

Julian also makes the remark, that using Jon's loader in SQL mode bypasses using the microservice APIs, which he considers "forbidden" in a multi-tenant environment for security reasons.