I had a 5 day transfer, and had implantation bleeding 4dpt, so the timeline would be correct for me. Then had positive poas at 9dpt, so again, appears to apply to me. With DS2 which was a natural pregnancy, i had implantation bleeding at 10dpo, and had positive poas at 14dpo, which fits in with the timeline. I agree though, its probably just a guide and not the rule.