I wondered why …and now I know.
March 18, 2020
World Quests
- Emissary Quests turn-ins no longer award 10 bonus reputation when a Contract is active. No other quest turn-ins are affected.
- Developers’ note: This seemingly random change was done to address an obscure bug that arose after the introduction of Echoes of Ny’alotha this past week. There is an internal limit on the number of different rewards that a single WoW quest can offer, and adding Echoes into the mix could push some Emissary quests past that cap in certain situations, preventing those quests from being turned in. Raising that long-standing limit is beyond the scope of a hotfix, and removing the conditional 10 bonus rep was the least disruptive fix in the short term
Here is the page link.