Silas' Sphere of Transmutation

This achievement requires you to have crafted the Alchemy Tool of the Trade from BFA: [item=156631].

You must complete a quest line to obtain the pattern to craft this and have 150 skill points in Kul Tiran / Zandalari Alchemy.

Complete the quest line [storyline=900] (Horde) / [storyline=899] (Alliance).

Craft the item by collecting:

[item=168143] x1 - Drops from [npc=135474] in [zone=9424] on any difficulty.
[item=168146] x1 - Drops from Priestess Alun'za in [zone=9028] on any difficulty.
[item=168144] x1 - Drops from [npc=133430] or [npc=133432] in [zone=8064] on any difficulty.
[item=168145] x1 - Drops from [npc=127484] in [zone=9327] on any difficulty.
Anchor Weed x50 - Can be purchased off the Auction House.
[item=162519] x1 - Crafted by alchemists. Check this url for materials needed depending on your rank.
[item=152668] x10 - You can scrap items from BFA at the scrapper in Boralus or transmute to obtain these. You cannot buy this on the AH but you can buy the items to scrap from the AH.

Was struggling to find the quest chain related to this because I guess I did it during BFA then ended up dropping Alchemy. After releveling and the quest chain not reappearing, I opened the alchemy trainer's inventory and there was a recipe to buy.

According to the game itself and Simple Armory's calendar, I earned this achievement on January 30th 2024. What i don't understand is how. I didn't have an active WoW account between January 2020 and August 2024. Was this achievement patched in and I retroactively earned it because I had met the requirements back in BFA?