When attempting to enable MyVIP in place of SSP IdP, the MyVIP state never changes to 'Yes' and never provided the new URL.
The ssp.conf file is not getting updated correctly, it isn't adding the correct URLs at the end.
The issue can be resolved by manually adding the correct lines to the ssp.conf file:
samlidp.enhancedSSP.enabled = Yes
samlidp.myvip.post.url = https://login.vip.symantec.com/viplogin/saml2/post/idp2fa
samlidp.myvip.relay.url = https://my.vip.symantec.com/api/authenticate-saml
samlidp.myvip.loa.url = https://login.vip.symantec.com