It's not calling into question the two days or 48 hours—I think they're the same thing. The issue was to provide clarity as to when the notice starts. If you wish to have “two days” as opposed to “48 hours”, it's no big deal. I used 48 hours to signify two days. I have no problem if you want to call them days as opposed to hours.
On February 5th, 2009. See this statement in context.