What happened to English -> Target language? It's just translate to English and that's it.
A/B test? I've heard people complain about this recently, so I think that it's not unlikely.
Maybe your account has been moved to the new web version?
There, the easiest way to change your base language is:
- On the home screen: Click on the flag next to your avatar
- click on "Add a new course" (https://www.duolingo.com/courses)
- go to the upper right corner, and click on the down arrow: ∨, to open the language menu for selecting your base language "I speak ........."
- click on the language you want e.g English
- click on the picture of the language you want to learn e.g Spanish
- a new webpage will open "Learn Spanish from English":
click on the button "Start course"