I have a report which has a slicer for fiscal month. When I load in new data each month, I update the default selection to the most recent fiscal month (new data) so users will will see the most recent data when they open the report. Additionally, users can always return to the most recent data by using "Reset to Default".
This is where the bug begins. Prior to the most recent data upload, I added the report to an App. Since then, I uploaded the most recent month of data per the procedure described above. The issue is that the default slicer selection saved to the report, but not to the App. The default state of the report is different depending on whether the report is viewed directly or through the App.