Bug. When exporting to Excel the SSRS report, the data exported is the first retrieved in the page.
What it means is if you run the report with certain criteria (C1), you see the result set and you export it to Excel,
then you change the criteria (C2), run the report again (i.e. you hit the View Report button which changes the on screen data)
- then export the new results to Excel, in Excel you get the result set for C1, not for C2.
Ie the screen shows C2 data but the Excel export is C1 data
It has the appearance of caching data
There is a workaround of closing the page and re-opening, but it's still a bug.