This was shipped in the first release of Bulk Import in Q2 2018. Bulk Import is available to the majority of our hosted customers.
This is planned as part of the Bulk Import feature scheduled for a Q1 2017 EAP.
As we are now in Q2 2018, I wonder if this is still being worked on, or whether we should seek alternative options.
This functionality has been included in the bulk import service which will be available by the end of Q2 2018 to customers hosted in the Boston data center.
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