Staying Strong – Above, I’ve attached 2 links that you might like to research. One is a powerful video and the other is a very informative paper, both discussing B12 deficiency. On page 10 of the journal (2nd link), 1st paragraph talks about how Hi B12 can actually point to a B12 deficiency (when not supplementing) I’ve heard that before but this is the first time I’ve seen it in a medical journal.
Hopefully this helps you understand the workings of B12 a bit more.
Charlie