When you analyse a group of sites containing multiple timezones, it may not be easy to understand what data is at every hour. We have two scenarios :
Historical data :
In this case, events are ordered according to the respective timezones of the sites in question. The reference timezone is the one of the user responsible for the query (desktop configurated timezone).
Example: "Site A" in timezone UTC+2, "Site B" in timezone UTC+4 and then my timezone from which I make queries in UTC+1.
For a day in the past, I'll see at 3pm the data for 3pm UTC+2 and 3pm UTC+4 on the same hour. Although these are events that didn't actually happen at the same time.
Real-time data (today):
In this case it would be the same, with the difference that the timezone of the user making the requests could be behind the timezone of one of the sites. To take the same example as for historical data, I won't be able to see the events performed in the minute for the site in UTC+4 because my timezone is UTC+1. I'll have to change my computer's timezone to the same timezone to see the latest data available in TR, or wait for +3h.