You can use any valid JIRA query with e-Reminders to setup a personal or group report.
If the query contains placeholder $USER and report is sent to a JIRA group/role, e-Reminders add-on will run query individually for each group/role member, replacing $USER with username of the member.
All Queries are run by JIRA user "e-Reminders" that is automatically created and associated with the add-on. Make sure this user has sufficient access rights to pull needed data.
For more details about the JIRA Query Language (JQL) see:
resolution = Unresolved AND due >= -3w AND due <= 20w AND assignee in ($USER) ORDER BY due ASC
Setup this one to run daily for JIRA users (or other group) using grouping by due date and recipients will get a nice email with an overview of approaching deadlines.
priority >= Critical AND status = Open and duedate is NULL
Administrators or project managers could run this or similar report daily to make sure critical issues are not missed in planning.