There are certain studies that indicate that the transplanted hair follicles from the occiptal region, can take on the degenerative characteristics of the hair follicles of that area, into which they are transplanted. This may be due to partly due to the trauma of the transplantation, but also due to factors that I'm not qualified or educated about, to inform you (reduction of potassium channels, etc.)
But generally, you are correct Mr. Steele; the transplanted hair should last you for the rest of your life.
The overall MPB process is progressive, and lasts the rest of your life, once it has initiated. The native hair follicles genetically programmed to degenerate, will do so, and the transplanted hair follicles, may degenerate (produce hair of lower calibre compared to when it was in place in the occipital region), but not completely die.