We're using the Customer Service (Napili) template on Spring '17 and the custom login page is not overriding the default. 

I have the following setting but going to the login page still displays the default page. I have followed all the direction in the documentation (https://help.salesforce.com/articleView?id=networks_customize_login_page.htm&type=0&language=en_US)

Is this a known issue? Is anyone else having this problem?
Thanks