If, at some point, we up2date our production 1.903 ACC installation to 2.0, and we already have several ASGs already in the dashboard that happen to already have RSA-based VPNs connecting them to each other, will the new ACC automatically detect those and display the appropriate information, or would we have to delete the remote ASG's VPN configuration and rebuild it using ACC?
ACC 2.0 will only display information about VPNs generated by the ACC. So other VPNs will not be displayed in the ACC. If you want to be able to monitor and use features the ACC provides (e.g. automatic update of the VPN when a network changes) you need to regenerate the VPNs with the ACC.