Downtime start and end times are defined automatically, based on what is configured in the Admin app. This means that it is not possible to change the start and end times of downtime. However you can split the periods in two in both the Operations app and Insight app.
This explains how to split downtime periods in the Operations app.
Choose a downtime period and click 'Submit Reason' (1.).
This opens the details for that period of downtime and shows the start time, end time and duration (2.). To split this period of downtime click the Split time button. (3.)
This opens the split time pop-up dialog, which again shows the start time, end time and duration. Use the split time field (4.) to assign the number of minutes at which the time will downtime period will be split.
So for example:
From: 7:15
To: 7:20
Duration: 5 minutes
If you split time at 2 minutes this will create two downtime periods (5.) one from 7:15 to 7:17 and the second from 7:17 to 7:20.