I think the last update from Atlassian on this was on: https://jira.atlassian.com/browse/JSW-6175
From that issue:
Atlassian Status as at November 2016
The Kanban Backlog feature is now available for JIRA Software Cloud. The release of Kanban Backlog for JIRA Software Server will be tracked at https://jira.atlassian.com/browse/JSW-15236 -- please add your votes and comments on that issue and continue to watch it for further updates.
There is a workaround suggested in the comments of:
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