I've got a bunch of transmog BoEs in my bags. I've got Legion Wardrobe and Can I Mog It? as add-ons.

I'm trying to go through the BoEs and find out which ones are duplicates (Altoholic helps with that A LOT...), and which ones are the least-restrictive alternatives for appearances I've already learned.

Can I Mog It? tells me that a BoE's appearance was already learned on another piece of gear (generally a quest reward). But the gear that I did learn it from (reported either by L.W. or CIMI) is from a quest. So there seems to be a hidden restriction (the minimum level of the quest).

Are most duplicate appearances going to be like that? A bunch of quest rewards, and a couple of BoEs that have a higher-level restriction?

I haven't found any MUCH lower-level restrictions yet (e.g., a TBC quest-reward armor replicating a level 20 BoE armor), but I wanted to make sure before vendors and disenchanting gets involved. :-)