This is where I will post my attempts to track all development progress in detail.

August 2021:

Firemoth Archipelago was rebuilt. Only the quest and the restored interiors left.

A lot of quests have been implemented in the Dominions of Dust area.

Andothren received another facelift.

Teyn and fort Ancylis were rebuilt.

First Shipal-Shin interior claims are opened.

A lot of work is happening in Thirr Valley area.

Bodrum NPC and dialogue work has begun.

A bunch of essential interiors was completed in Helnim.

A lot of new unique buildings appeared in Firewatch.

Now there is a Telvanni tower on Bahrammu island.

Baluath Clan quests have great progress.

Main questlines of Andothren, like the Guild of Mages and the Fighters Guild, have got new quests implemented.

The Imperial Legion questline in Firewatch is almost complete.

Miscellaneous quests the Remnants of Resdayn, the Statue, Lost in Transit, Poisoning the Well, Khajiit Ambassador Brother, the Ashlander Wife, Nirn-bound Saint, Ring of Euphoria, Vodunius Nuccius Part 1, Proud Redoran, Brother against Brother, My death, When Love Crosses Rivers, Clueless Eggminer and House for Sale are ready to be playtested.
 

TR Progress Report September-October 2021:

Interiors that were reviewed and merged (or waiting to be):

Hadrumnibibi - a daedric ruin north of Almas Thirr - now has a sprawling underground complex.

Velothi Mountains Dwemer Ruin #1

Velothi Mountains Ancestral Tomb #1

Velothi Mountains Cave #7

Velothi Mountains Cave #5

Velothi Mountains Daedric Ruin #1

Velothi Mountains Cave #6

Stormgate Pass #2 - the first interior of Shipal Shin.

[ITO] Firewatch, Iron-Grip's Weapons (refit)

[ITO] Tel Rivus / Andvaryon - the new Telvanni lord in the north.

Fort Ancylis Cutter #2

Remnants of Resdayn: Dusara - a quest-related alternative look for the dungeon.

[ITO] TEM Ghostrunner - a cutter that patrols the northern waters.

Ald Erfoud Ruins.

Fort Ancylis Cutter #1

Stendarr Tower Haunting Cutter - a patrolling ship to complement the original OE quest.

Shipal-Shin #4

Ancestral Tomb #2 - another fruit of the first Shipal-Shin interiors.

[ITO] Firewatch, Census and Excise Office (refit).

[ITO] Helnim, Lariast: Trader (Refit).

[ITO] The Web of Air - one more ship to Imperial flotilla.

[ITO] Helnim, Imperial Cult Chapel.

[ITO] Firewatch, Grand Chapel of Akatosh.

Ashlands Dwemer Ruin #3 - Bazak, a dwemer outpost in the west.

[ITO] Firewatch, Dustmoth Legion Garrison.

Bodrum - Lord's Manor.

[ITO] Firewatch, Brandir Zabaal: General Supplies (Refit).

[ITO] Helnim, Ensalda's House (refit).

[ITO] Firewatch, Guild of Mages - now the guild has a dedicated building.

[ITO] Firewatch, College - the heart of imperial knowledge in the East.

[ITO] Firewatch, TEM Saber of the Straits - an imperial galleon.

Teyn Ancestral Tomb - not a labyrinthian hell anymore.

Thirr Valley #2 Plantation #2

Thirr Valley #2 Plantation #1

[ITO] Firewatch, Briricca Private Bank

 Interiors done and ready for review:

Shipal-Shin #4 Ancestral Tomb #1

Shipal-Shin #3 Ancestral Tomb #1

[ITO] Firewatch, The Howling Noose (Refit).

[ITO] Helnim, The Red Drake Inn - both taverns got redone.

[ITO] Firewatch, Drakelight Beacon - is now shining.

Shipal-Shin #8 Ancestral Tomb.

[ITO] Helnim, Census and Excise Office - what if you were to start your game here?

[ITO] Firewatch, The Queen's Cutlass (refit).

Adavrin Netch Ranch #5, Guard Tower.

Shipal-Shin #8 House #2 is ready to be populated.

Thirr Valley #3 Mine #2

Shipal-Shin #4 Tanna Farmer's House - his crops are great for restore magic potions.

Ald Marak #3 Adavrin

Netch Ranch #2

Thirr Valley #4 Shipwreck - is now created to remain destroyed. Thank you, all, who have spent their time on creating these. And thank you, reviewers, for carrying that burden of checking and polishing our work!

 Interiors that undergo a review:

Thirr Valley #5 Cave #4

[ITO] Helnim, Zafirbel Bay Company (Helnim Hall) - meet a new trading company and a new background to the old Helnim.

 Quests and Dialogue work reviewed:

Lost in Transit - a sad story about a lost son and an irresponsible adventurer is ready to be merged.

NPCs and General Dialogue: Omaynis.

Dialogue Update: Teyn and Fort Ancylis.

General Dialogue: Map 4 - general dialogue for Dominions of Dust lands.

Vodunius Nuccius Questline Part 1 - continue the adventures of one of the first NPCs you encounter in the game!

 Quests pending review:

The Statue - decide the fate of st. Felms's image in Omaynis.

Certificate of Credibility - get yourself welcome in Andothren.

The Proud Redoran - solve a problem of an impoverished old warrior.

Brother Against Brother - help or destroy a family.

 Exteriors:

Shipal Shin 08
Shipal Shin 07 These exterior locations that consist of dozens of cells were reviewed and merged with the main file. Every such location takes months or even years to make. Four of Shipal-Shin exterior claims remain in development (see the map below). As well as two for the Thirr Valley region. Also, our exterior devs continue to carry on the task of redoing Roth Roryn exteriors. An extremely valuable work that is hard to document due to its nature.

You can see, that Tamriel Rebuilt was far from sitting idle these months! But another great work was made by the Asset Department as well. And here is my first attempt to document it in the report. Asset Department in September-October 2021:

 Assets created and merged:

Note To Self editormarker - a special marker for leaving developer notes in the cell.
Edited Redoran interior pieces - a fix for vanilla shell pieces.
Firewatch cobblestone texture - new texture for an old city.
Othreleth Woods Suj Sprout - a beautiful model of a plant that smells horrible.
Red Leaf Tree - a new tree to constitute Othreleth Woods.
Imp SetMw Tower Interiors - 3 new tower interiors.
Varga - Othreleth plant with dark leaves.
More generic TData enchanted weapons and armor [battlespire items] - dozens of new enchanted items (with vanilla meshes) from TESA: Batllespire.
Random Jungle plant (EoA) - a contribution to the future Argonia province.
Imperial rugs and tapestries - a dozen of new rugs and tapestries to decorate your imperial dwellings.
The Polyhedrascope - an intriguing headpiece for an intriguing GM questline in Andothren.
Prerelease Tapestries - a set of 18 tapestries and banners seen on prerelease screenshots of the game.
CM moss texture - a land texture for the Clambering Moors region.
Volcano mesh for ashlands - a new land texture to replace Molag Amur textures in Armun Ashlands.
Ebony Clutter Update - a new version of Ramiros' models borrowed from OAAB.

Tumtum Revision - fixes and improvements of this fountain-shaped plant.
Stones March Armor - a bulky armor for Redoran Orc hunters (see image below).
Stones March Gauntlets Reweighted - a hot-fix for the armor.

Roa Dyr Merge - a merge of architecture pieces for the settlement to improve FPS.
Wolli's Revised Oak Trees - fixes and improvements.
Azura Coast Snow Menhirs.

Othreleth Woods Shroud Cap - a human-sized pale mushroom with veil skirting.
T_ImpSet_MW Single Pillar Strut - if you have worked with the imp set, you'd know that the value of this little plank would be hard to overestimate. Othreleth Woods Rockburst Redo - a menacingly looking red plant.
Plateau rocks - a set of new rocks for Khalaan.
Spyglass - a good piece for naval-themed interiors.
GITD Support Addon - more windows now glow in the Dahrk.
Window mesh fix - a hot-fix for the windows.
Dunmer Round Rugs - 13 new round Dunmer rugs.
Bad pauldron dremora replacer - a fix for an old TR dremora.
Some improved and optimized Indoril meshes.
[ITO] Cathnoquey Bronze Weapons and Urns - objects from the island of Cathnoquey that could be seen in the new Firewatch.
Othreleth Woods Coral Fungus - a set of colorful coral plants (fungus).
Othreleth Woods Glowing Mushrooms - majestic stuff.
Andothren Buildings Part 3 - Andothren Port Authority tower and Warehouse/Apartment block.
Com M Cabinet - an unused good-looking vanilla mesh is now restored for you to use in imperial buildings.
[ITO] Gallows - a grim tool of justice that remains in Firewatch since the times of unrest.
[ITO] War-Banner of Prince Bashomon - an artifact from the farthest Padomaic Island, Esroniet.
"Preview Enabled" Global - a script to build upon when working/playing with TR_Preview.esp.
Redoran Watchman Redo - a glorious redo of a glorious armor set.
Firewatch Chapel Legion Set Additions - new imperial staircase pieces and a light lecturn.
Othreleth Woods Poison Bloom - a dangerous but pretty plant.
Othreleth Woods Cupling Touch-ups - an improvement of the plant mesh.
[ITO] Chapel Set LegionMw Retex - 6 new exterior pieces for imperial structures.
Drumpear - a plant, a tasty meal, an ingredient, a musical instrument, a playing ball, and a lucky charm found only in Shipal-Shin.

Improved Shipal-Shin bushes 01–07.
Fixed Nord face meshes - fixed animations.
Old Gate set modern-update - improvements for the old TR gates mesh.
Improved bookends - now you can actually fit them in the bookshelf.
Yam Orb - a cave plant that looks like a swan and glows (see image below).

 Bugfixes:

The Eastern Quarantine Book Mesh fix - removed the inscription.
Swamptroll-Fix for OpenMW.
Stranded quest fix.
Very slight NIF changes - for a balcony and a table.
Vampire Fixes - a number of bug fixes related to vampires.

 Assets - candidates for including:

Hlaalu Brevur statue for Narsis - a lore-friendly statue of renown Hlaalu made by R-Zero.
Peddler's Buoy (Tulband) - a flower for Othreleth Woods.

 Literature merged:

Horoscope for 3E 427 - now you'll get to know more about your fate.
[ITO] Firewatch: A History - find out a backstory of the imperial capital in the Telvannis.
Additional generic books - business ledgers and accountant books for relevant interiors.
Lichdom: A Trap, an Escape - a book about becoming a lich that explains the difference between a mortal and immortal lich.

 Literature that awaits review:

Broken Truths - a proposition from an esoteric Mystic to his student, a skill book. The Asset Department was active as never before. Just look at all the flora that has been created for Othreleth in the expanse of two months! Or the invaluable shell additions that make interior work so much easier. Thank you all for your contributions big and small! You are wonderful!