Currently, if a user has the Schedule an Issue permission, https://confluence.atlassian.com/jirasoftwareserver075/scheduling-an-issue-935563112.html, they have the rights to both set a due date, and, despite the documentation not saying so, rank an issue on a JRIA Softward board.  I need to allow our product team to set priority of an issue, without being able to say when it's due (they abuse the right to set due dates and often set arbirary dates). 

These two permissions should be decoupled, or at least documented in the above page.

Background for reqeust: https://community.atlassian.com/t5/Jira-questions/Rank-Issues-without-Schedule-Permission/qaq-p/652882