Thanks to Edvin#1139 for the Timeline
Mojang

10 November, 2010

Minecraft Alpha v1.2.2 is released

Minecraft Alpha v1.2.2 is released, and with it comes the first time we get a look at the image.
JoeIsMoe

January 15, 2012

Joeismoe's forum post

JoeIsMoe makes one of the first known forum posts asking about the origin of the pack.png image before SalC1's.
LicketySlip

February 5, 2014

First Clue

This post by LicketySplit is the first forum post after JoeIsMoe that leaves an actual clue about what the seed could be. The seed "Mojang" has since then been searched but the structure was nowhere to be found.
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January 14, 2020

SalC1 posts a video revolving the image.

SalC1 posts his video where he discusses and questions the photos origin.
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January 14, 2020

SalC1 makes a Tweet

SalC1 posts a Tweet asking well known Mojang employees if they can remember any information about the photo.
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January 14, 2020

Notch gets involved

Notch, creator of Minecraft, gets involved in the hunt on Twitter and claims he does not remember taking the photo himself.
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January 14, 2020

Dinnerbone Responds

Dinnerbone (Mojang employee) suggests the world seed "flyby". The Flyby seed was then searched but to no success.
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January 14, 2020

Following cloud pattern

Discord user "Kanibal" suggests the X and Y axis can be found by following the cloud pattern shown in the image.
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January 14, 2020

Recreation Server Started

A Recreation Server was started by Ry for users to recreate the strcture from the photo in a 3D enviroment to help train AI's that could come to help. The server is still up and has a very close replica of the hill.
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January 15, 2020

Alx. leaves a comment

Discord user Alx. claims to be a former Mojang employee and says the the image could have been taken in a private build of Minecraft. This has yet to be confirmed or denied.
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January 15, 2020

BrayCam and gsmack

Discord users BrayCam and gsmack determines the world axis by the lines in the water. The lines shows the face of the hill is on the X axis.
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January 15, 2020

First 3D render

User Brastin3 creates the first block by block 3D render of the image.
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January 15, 2020

SalC1 at Mojang

SalC1 sends a Tweet directed to Mojang themselves asking about the origin of the photo.

January 16, 2020

Finding the light level

Discord users Blob and Derufai determines the light level of the photo by using Metadata and converting convert pack.png to it's original gamma. Light level found was 14.
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January 17, 2020

A New Approach, AI

SalC1 publicly announces on his Discord that the original resolution of the image is simply too low to get any good information from it, and that we will start using AI to upscale the photo into better quality. For this, we need sample screenshots and a screenshot dump channel is created for members to dump tons of screenshots to help train the AI.
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January 18, 2020

AI submissions closed

The screenshot submission for the AI is closed, checking out at 1.7 MILLION screenshots.
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January 21, 2020

First Upscale Released

The first truly AI upscaled image created by user James Bond was released on the SalC1 Discord server
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January 22, 2020

Fabric Ported to 1.2.2

Discord user EarthComputer has ported the modern mod loader "Fabric" into Alpha 1.2.2, making it possible to make and use mods.
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January 22, 2020

Second Upscale Released

A new insanely detailed upscale with a resolution of 512x512 was released by user James Bond, which is extremely helpful in the process of reversing the seed based on block placement
 
Joeismoe's forum post
January 15, 2012

Joeismoe's forum post

First Clue

SalC1 posts a video revolving the image.

SalC1 makes a Tweet

Notch gets involved

Dinnerbone Responds

Following cloud pattern

Recreation Server Started

Alx. leaves a comment

BrayCam and gsmack

First 3D render

SalC1 at Mojang

Finding the light level

A New Approach, AI

AI submissions closed

First Upscale Released

Fabric Ported to 1.2.2

Second Upscale Released

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