TF from 20 to 0 Expired Tumblr

In the past month, I built a bunch of expired web 2.0 and I'm beginning to see the first good results. But, rechecking the metrics of them, an expired Tumblr who had a TF of 20, now has a TF of 0 with the exact same links. I know that TF is a volatile metric, but being so volatile it means it is inaccurate. Is it an isolated case or is it fairly common? Thanks (sorry for the broken english).

TF is built up with the TF of the incoming linking domains. With majestic, you can be explicit about this topic: just check which links have been lost, that lead to that new 0 TF. You can check historic data if you have the Majestic account. Going from TF 20 to TF 0 is not common, but fairly possible, specially in this kind of 2.0 that tend to have incoming links from a feed or other 2.0 that linked them for a while.
This is why metrics could be useless most of the time: if you don't see the URL profile, you can never be sure with a high degree of confidence, about the "stickiness" of each incoming link.

I think the Tumblr has redirect links, and the owner shifted them to a new web 2.0 or site. You can check it by looking for lost links.