Interesting and somewhat disappointing that it took a year for anyone to notice that it had disappeared. The appearance generated quite a lot of interest.
(Of course, I'm as responsible as anyone else for not noticing. I wonder if it would be possible to build a service to proactively check for their disappearance?)
I don't think it took anyone a year to notice it had disappeared. Where did you get that information? The report for the first half of 2013 where the original canary appeared wasn't even released as of a year ago. It was released Nov. 5, 2013.
Furthermore, this document (https://www.apple.com/privacy/docs/upd-nat-sec-and-law-enf-o...) provides credence to the possibility that the NSA requested information from Apple after the Nov. 5, 2013 release as that Jan 27th, 2014 release directly mentions that it replaces the previous notes.
(speculation ahead)
This, along with the knowledge that the canary is now removed, implies that the NSA requests were the core difference in the numbers, in my opinion. This would place the time of NSA disclosures to sometime in late 2013-very early 2014, I would imagine.
He probably thought the report missing the canary was published at the end of 2013 given that's the name of the report and the date in the filename. Understandable mistake.
The metadata in the PDF file says it was actually created on August 27th of this year.
I'm sure it could be found with a web archive or a quick search, but I personally believe it is irrelevant as it would not make sense to release the 2nd half 2013 report before the 1st half 2013 report. This means the 2nd half 2013 report had to have been released after Nov. 5, 2013, but beyond that, it wouldn't make sense to release the 2013 report before the year is over, would it? This leads me to believe it would be nearly impossible for this canary to have been missing for over a year.
Edit: ugh, hate when people edit after I already responded... It would literally be impossible for this canary missing to be over a year old. The news of the canary's existence didn't even break over a year ago (from my research).... I don't understand why this point is even debatable.
(Of course, I'm as responsible as anyone else for not noticing. I wonder if it would be possible to build a service to proactively check for their disappearance?)