A family of Microsoft spreadsheet software with tools for analyzing, charting, and communicating data
If I understand correctly, you are using a UNIQUE function in Column E for the data in Column A and want it to be sorted alphabetically regardless of how you sort the data in Columns A:C. You can put a SORT function in front of the UNIQUE function to sort the results of that function like this. This will sort the unique results no matter what order they are in in Column A.
=SORT(UNIQUE(A2:A16))