Good news! Worklogs - Time Tracking and Reports team has just released a new version, and since you use Jira Server you can decide to upgrade at any time! All that is needed is a click of a button in the Apps management screen on your instance!
Improvements:
Reports can now be saved with a specific date range selected using the date picker. It allows more precise and customized reporting.
We have improved the report-saving functionality, enabling users to save more reports.