When you run a report on one monitor for February, the times are correct.
When you run a report on a group of monitors (e.g. two monitors) the time goes from 28 days to 56 days.
This is not logical. February only had 28 days, not 56 so uptime should be 28 days if it was 100%, not 56 days.
It seems that the logic for calculation of the times on groups of monitors is too simple and makes no sense if you have multiple monitors in a group.
The time just gets multiplied by the number of monitors...
I guess the confusion is regarding whether the two monitors overlap or not.
Let's say those two monitors measure different systems. If one monitor was update 100% of the time (28 days), while the other was down 100% of the time. What should the total up time be? 28 days or something else?
My expectation would be that if I create a group of monitors for reporting they would be combined. Maybe have a toggle if necessary to say if you want them working as you have implemented it - stacked - or the second option - combined.
Stacked would work as you have it right now.
Combined would take into consideration if they were overlapping and treat them as 2 parts of the same timeline, two aspects of the same system, either of which could be considered an outage of the "group".
e.g.
1. if first monitor was reporting outage on a particular day between 10:12 AM and 10:22 AM; and the second monitor in the group was reporting outage on the same day between 10:20 AM and 10:35 AM, the "combined" outage would be 10:12 AM to 10:35 AM - 23 minutes - to be counted against that 24 hour period.
2. if first monitor was reporting outage on a particular day between 10:12 AM and 10:22 AM; and the second monitor in the group was reporting outage on the same day between 10:25 AM and 10:35 AM, the "combined" outage would be 10:12 AM to 10:22 AM and 10:25 AM to 10:35 AM - 20 minutes - to be counted against that 24 hour period.
3. if first monitor was reporting outage on a particular day between 10:12 AM and 10:22 AM; and the second monitor in the group was reporting outage on the same day between 10:13 AM and 10:21 AM, the "combined" outage would be 10:12 AM to 10:22 AM - 10 minutes - to be counted against that 24 hour period.
Hope this helps understand how I was hoping the "group of monitors" report would work, seeing the "group" as an entity, group of the same sub-elements, not as a stacked group of different sub-elements.