Copying a post from the US forums that I didn’t see have an answer. Checked wowhead and a few other places but haven’t found answers.
While obviously, some Tier gear drops from raids, not all of it does for all classes. Some tier set transmog appearances (especially for no tier slots) must be converted at the Catalyst to get the appearances for the full transmog set. For Raid Finder and Normal transmogs. you could get gear from world content and convert it to the respective appearances at the Catalyst
For season 1, this gear comes from Forbidden Reach or RF/Normal Vault
For season 2, this gear comes from Dreamsurge vendor, or RF/Normal Aberrus
For season 3, this gear comes from the weekly Emerald Dream quests, or RF/Normal Amirdrassil.
However, as all raids become Awakened (in a few weeks), the gear from their will no longer convert into its original tier season set, but into whatever set has been voted for Season 4.
For seasons 1 and 2, the Forbidden Reach and Dreamsurge are still options (I believe). However, the gear from Emerald Dream already converts to S4 tier, not season 3. That means that will also no longer be a viable method for older season transmog appearances
As an example, the ONLY piece missing from my warrior’s Season 3 transmog appearances is the RF belt. I have full N/H/M sets. So how can I get the belt? If I’m lucky to get a belt drop from Amirdrassil on a non-awakened week, I can convert that? but in a few weeks, it will be permanently awakened.
Likewise, my druid is only missing the RF tier helm. I’m hoping that non awakened Amirdrassil RF can drop it still (or be converted appropriately), but I cant get it by converting Emerald Dream drops anymore either.
Am I wrong about this issue? Am I missing something?