I may have this completely wrong, so if I am being an idiot, someone please tell me to shut up :p
I thought that, whenever you update your signature it should update your signature on all of yours posts, past, present and future?
When I updated my signature yesterday, it didn't update my signature on past posts, only the posts made after the signature change.
Am I right in saying it should change the past posts as well? Or does it only show on future posts?