Armorer quest and Blacksmith quest are bounded WTF

Q. Why can I no longer undertake the rank 20 armorer quest after accepting the rank 20 blacksmith quest?
A. The blacksmith and armorer class quests have been grouped together. Though players are free to choose either of the classes they wish, they will only be able to complete the quest for one of the two. For example, if a player has undertaken the rank 20 blacksmith quest, the rank 20 armorer quest will become unavailable. The player will, however, again become free to choose either blacksmith or armorer for the rank 30 quest. Quest content and rewards will be adjusted to fit the class chosen for the each quest.

* Quest progress for both classes can be viewed by opening main menu >> Journal >> Blacksmith & Armorer Quests.