IAOAOI
July 8, 2019. A block dedicated to Cariga Bright, "someone absolutely not existing whatsoever". The name is a clue, says the author. The question is IAOAOI. Format (solution)., digits 561, copypasted this time.
u/AirShark90 flips a table. u/martypyouknowme tries I Am Of Asian Origin Indeed. Close in spirit. u/Quantris tries I AM NOT SATOSHI. Not that either.
A signing pen
Then the updates. The author wants to sign a message with the funding key. First the key has to come out of the Tulip Trust. Then it's signed "with my signing pen, right on the white space under the message on my display". Sound familiar?
The message is I am a young woman of Japanese ancestry, who is very smart and sincere, Aoi Nakamoto. The second time, I a and Aoi are in bold. Vowels IAOAOI, hiding in plain sight.
The answer is I am omnipotent Aoi. u/puzzleponky had it before the hints, only in capitals. The claim confirmed at 23:17:02 UTC on July 10, in the same block as block 64. Good message for Cariga Bright to sign in 2029, says the author.