Unable to add CNAME for .app domain

Thanks! I have waited for propagation to happen over night, and can confirm that whilst not totally propagated, it has propagated to my current DNS. I have tried to access my site from my current location, and my proxying to various different locations and all give me the below error:

I found many other forum posts relating to this issue of which [Resolved] Err_ssl_protocol_error - #18 by icexuick is one. Am I doing something wrong or are there some SSL issues at the moment?

Thanks
Dan