User blog comment:Crazywarfire/My Dishonored Theories/Explanations./@comment-3202167-20130305140007/@comment-27202257-20130306015128

Hmmm, I had always assumed that Dead Drop was the first of the two (the other note is Letter to Daud, by the by), but looking at it again there's really nothing to definitively show which one was delivered first. You could really interpret them as being sent in either order.