It is actually possible to make a copy of the existing report and make the changes to sort by time. Please see the attached document for where you can locate this to make the changes (ReportNavigationAndDefinition.pdf)
You may also refer to the Configuration Guide, chapter Reports in the Identity Manager
for more steps/instructions.
Please note, there are several steps necessary (changing the report, adding new time range parameters, setting the new report into Designer as new tree and disabling the predefined report, or let them both exist in parallel).