Cannot access IMAP server, get "Temporarily blacklisted IP Address" on phone and outlook.

Yesterday, my wife and I both started getting prompted for our passwords on our comcast.net email accounts on both outlook and our iPhones.  On the iPhone, I the error "Server code "ALERT:, server message "Temporarily blacklisted IP Address". 

Note xfinity isn't in our new location, but we've been accessing our legacy email for over 8 years here.  If I connect with VPN enabled, it works on the PC so it's something with our MidCo IP address which has been working for several months since we switched in the summer.