Problem
Start date end date filters don't work. In particular it is not clear whether dates refer to issue fields (like creation date) or worklog date.
Solution
It depends on the report type, in case of reports based on Worklogs (Timesheet, Pivot by User, Pivot by Status, Timespent), dates refer to Worklog Started Date, in other cases (Time Tracking, Time In Status, Time Balance) dates refer to issue created/updated date.
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