#11 - Dec. 7, 2012, 11:44 a.m.
Ok, I checked with Security, and these situations appear to be a simple misunderstanding of how the authenticator works.
When you log into an IP (or an IP range — a cluster of nearby IP addresses) you will receive a message asking you to verify that IP as “accepted.” This is commonly called “whitelisting” the IP.
If you log into an IP or IP range in the future, you will not get a message because you’re already said “This IP is ok — allow my account to be accessed from this IP.”
In the future, we will allow you to always require approval of an IP, even if it’s you logging in for the fourth time in a day from the same computer at the same location. That will be your choice, and many people recommend that you do choose that option once it becomes available.
But right now, in beta form, the authenticator “whitelists” the IPs you approve and then does not ask you to approve them again.