So, my app timezone is correctly set (to AEDT - Sydney). When the field techs are out there doing their job, the app timestamps the record via record rules.
So in my interface I have created a report page with some pivots and some graphs, and one pivot shows the work achieved by each technician each day.
The problem is that the date shown on the pivot table is equal to the date if it were in another timezone. NB: the date in the records of the database is correct with the correct timezone, it is just the pivot table labels that are wrong.
This means that the report is all wrong, showing work is occuring on the wrong days. And as the timezone factor changes at a time, it is not like the whole days work is appearing on the wrong day, it is spread across the days.
As the time itself is not shown, only the date, i need to manually review the numbers, and my best assessment is that it appears that the timezone that pivot table is using is somewhere in the US.
My theory is that the pivot table does not take into account the timezone setting and is using a default timezone. Of course, my alternate theory is that i am an idiot and have forgotten to set something somewhere (myapp timezone settings are set correctly)