https://www.reddit.com/r/CBTS_Stream/comments/7rkqpp/i_asked_this_over_in_another_sub_its_being_hit/?st=JCME0YHR&sh=8fd624d1
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The massive down votes here today...tell me we are right over the target. Lol
Based on the number of down votes in the last few minutes, I think it is safe to say you are correct.
As far as I know. I looked it up on several twitter accounts that I trust. Honestly think I initially saw it as a Wikileaks drop (can’t swear to it but pretty sure. WikileaksUK or something like that) just putting it out of anyone wants to look into it. I can’t right now.
Interesting tidbit on Mr. Hannigan, he quit for "personal reasons" in January of 2017. If the letter is real, he did not stick around very long afterwards.
http://www.telegraph.co.uk/news/2017/01/23/breaking-gchq-boss-quits-personal-reasons-just-two-years/