I have WSUS under "Update Source and Proxy Server" port number is set to 8530. Computers is set to "Use the Update Services Console."
No, the port 8530 setting does not refer to "update source and proxy server".
WSUS itself, if you use WS2012 or WS2012R2, is published/listening on port 8530.
Older versions of WSUS listened on port 80.
When you set the GPO for clients configurations:
"Specify Intranet Microsoft update service location", and in this, you set the address of your WSUS (so your clients can locate/connect to your WSUS), because you are using WS2012/WS2012R2 you must specify the 8530 port, for this setting.
e.g.:
Set the intranet update service for detecting updates:
http://wsus-01.contoso.com:8530
Set the intranet statistics server: http://wsus-01.contoso.com:8530
https://technet.microsoft.com/en-us/library/dn595129.aspx#BKMK_Comp14