The community link removal is something that was updated but not directly related to the Security update referenced in some communications.  You can confirm your version by going to HELP and ABOUT PS and checking out your version and comparing it against the information we have in the Security update article, you must be on the version listed or higher.

Here is information about the removal of the community link: https://accountants-community.intuit.com/announcements/1743956

Here is the information (including version) for the security update: https://accountants-community.intuit.com/articles/1736700-important-security-update-for-proseries