How do you change the label for different field views, but for the same field?
The label changes based on the currently selected record type. If the record type field is not filled out, it will say ‘default’ instead.
So if you want to change the labels for a record type, be sure to have open on the screen a contact record for that record type. This way when you change the labels via the screen interface you are changing the label for record type displayed.
To change the actual label.
1) Right click on the label and select "Properties"
2) On the "Profile" tab, change the value for the "Label used..." field.
Note: Before making any change double check the the right record type is displayed on this tab.