Why no 'last activity' date in posters profile?

While looking at a long time posters profile I noticed that there is no ‘last activity’ date listed and was wondering why this is so.
I hesitate to publicly say who it is, and I’m fairly sure that said poster was never banned. If the Mods would rather I PM them about this, I will.

This thread was done just a week or two ago here.

One thing that you may not know is if the person is set to “invisible” mode, they will never have a “last activity” date showing.

Invisible mode is correct. Or they’re posting from Area 51.

I tested Invisble last time. I’ll go test the Area 51 theory.

nm