This is a compilation along with other rumors that are floating around put together. They were on B&C and did get removed or taken down.
Here is what was said, as preserved on from B&C on Reddit
BOLTERANDCHAINSAW LEAK:
'Heard third-hand from the same person that provided me with this rumour; to be digested with the usual pinch of salt.
In January 2022, we will get:
T'au:
Codex with reworked plastic Darkstrider
After January 2022, we will get (in no as-of-yet defined order):
CSM:
Plenty of new kits for 9th Edition.
Regular Possessed, Bikers, Chosen, Warpsmith, Cultists (BSF-style), Renegade Guard (BSF-style), human mutants, possessed humans (the latter two are monstrously horrible. Think of the Greater Possessed but cranked up to 11), cultist standard bearer (character), cultist character with bodyguards.
Chaos Knights:
New Knight variant with Codex
Craftworld Eldar:
A massive, but incomplete, update of Eldar
Without a specific date but in the pipeline:
Squats
World Eaters
Daemons
Astra Militarum with veteran-style Cadians. Two new regiments are also in the works. New Kasrkin and new vehicle, designed to fit between the Leman Russ and the Baneblade.'
4CHAN LEAK:
' Roadmap "leaks"
September 2021:
New Ork releases alongside a Black Templars army box, similar to the Sisters' and Beast Snaggas' boxes, containing:
Codex Cards Crusader Squad (6 Initiates and 4 Neophytes) Emperor's Champion Seneshal Redemptor
October and November 2021:
Complete BT release with
Ancient, Helbrecht, Grimaldus, Emperor's Champion, Seneshal, Initiates (6 Marines with Intercessor CC equipment or auto bolt rifles), 4 Neophytes (boltguns or chainsword). The Crusader kit will have options for a Sword Brother unit leader with cape, and there's a 15" AP-1 flamer.
The Sword Brother kit will have plenty of CC options and the option to make a Marshal (like with the Custodes Warden kit that gives you the option of making a Captain).
There will be two Crusader Squads: the old one that everyone knows and a new one made up exclusively of Primaris. The latter will be 5-11 Primaris Initiates, 4-8 Primaris Neophytes, and 1 Primaris Sword Brother. Neophytes will have 2 W and 2 A like other Primaris.
There'll also be a conversion/bitz/upgrade sprue that will have Templar relics on it (so-and-so's helmet, the sword of such-and-such, etc.), shotguns for Neophytes. and more customisation options like extra arms (Neophyte holding a helmet), or backpack-mounted candles. There will also be a multi-melta which will become a BT vehicle option. It'll replace the stubber on Primaris vehicles.
There will also be a Kill Team box with Sisters Neophytes (new kit and unit entry) vs T'au Pathfinders (upgrade kit) with existing Imperial city terrain.
December 2021:
Custodes and Genestealer Cults with a box, similar to the Hexfire (TS v GK) one, containing both factions, with a new character for each: GSC Saboteur and Custodes Lieutenant.
From the 4chan leaks/predictions guy that was right so far this year.'
ELDAR LEAK THAT'S FLOATING AROUND MAJOR SITES:
' Eldar Rumors
Combined Codex: Craftworlds, Ynnari and Harlequins
New Avatar of Khaine a lot bigger
Shining Spear & Warp Spider phoenix lords plus plastic Baharroth
Plastic Warp Spiders and Swooping Hawk kits
Plastic shining spears/ranger bike dual kit
Battle Focus will now be a d6 jump shoot jump ability
New Harlequin mechanic, Quins can fit multiple squads in one transport
A system very similar to miracle dice
-1D on all wraith units'