Case sensitivity settings can alter reports, specifically when using segments/filters.
NOTE: Conversion Variables (eVars) are not case sensitive, only props can have their case sensitivity changed.
Effects of this change:
Segments/filters may not return expected results on the historical data or for date ranges that cross the date of change.
For example, if you have passed XX, xX and Xx as values in a variable, post the settings are changed, applying filter/segment for XX may return values XX, xX and Xx. This is because when changing the case sensitivity settings, Analytics actually changes the underline hash values that are used to store key values in the database.
Toggling ‘Ignore Case’ can cliff line items that appear identical. The cliffing can happen in the same-case values as well.
See the below graph:
Any page names or props that used any uppercase letters would be assigned new hashes by switching to case insensitive.
More information is available in the help document.