Problem:
Junk box summary not going out or going out at wrong time:
Sometimes user will complain they are not getting junk summary at all or getting at wrong time ( other than the time mentioned on junk summary settings page)
Junk summary sending is dependent on a file on the system called "lastnotified_race" file.
This file has a time stamp of when the last junk summary was sent out. If for some reason, this file gets corrupted than it will not send the junk summaries to user or may send it out at wrong times.
Resolution:
You can refresh this race file by using a CLI command to fix the issue.
The steps to do the same are as follows: (as shown below)

Once you run this command, set the junk summary to go out at the time you want it to be sent to users and it should go out at the right time.
Note: Make sure the time on the device is set to the right time and zone.