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Salvage Yard
Tier-3 salvage recovered from Follower missions no longer has an independent chance to drop an uncommon (green), rare (blue), or epic (purple) item and will instead always drop one of them. This change is intended to reduce overall item spam without affecting their value. Existing chance for Tier-3 salvage to potentially also contain an uncommon Tier-2 salvage item remains unchanged.
Follower Weaponry and Armor Set tokens (War Ravaged, Blackrock, Goredrenched) no longer drops from salvage. Weapon and Armor enhancement tokens that can upgrade a Follower's weapon or armor item levels will continue to have a chance to drop from Salvage Crates.

Above are the changes to Big Crate of Salvage , which are rewarded from level 95+ Garrison follower missions. Now if you do not care about chances at random uncommon, rare or epic items you will want to save them. Only do this if you don't have a lot of follower enhancement tokens like Weapon Enhancement Token. Currently, in 6.0 Tier-3 salvage crates have a chance to give Blackrock Armor Set (Upgrades follower ilvl to 630 from any ilvl below) which in 6.1 will no longer "drop." The reason you might want to save your crates is due to the fact that all your Followers are item level 645+. Any "set" token will be useless to you and if you open your crates before 6.1. The chance of getting a useless "set" is there, which won't be the case in 6.1. The only way to get your follower item level 645+ is through enhancement tokens which is the only follower item that can be obtained in Big Crate of Salvage once Patch 6.1 goes live. Reminder the cap for follower item level in 6.1 is 675.

Math Stuff (If all 25 of your followers are item level 655)

Weapon Enhancement Token = +3 ilvl, 7 Weapon + 7 Armor = 14 Tokens to reach ilvl 675 * 25 Followers = 350 Uncommon Tokens
Striking Weapon Enhancement = +6 ilvl, 4 Weapon + 4 Armor = 8 Tokens to reach ilvl 675 * 25 Followers = 200 Rare Tokens
Power Overrun Weapon Enhancement = +9 ilvl, 3 Weapon + 3 Armor = 6 Tokens to reach ilvl 675 * 25 Followers = 150 Epic Tokens