Adding my personal experience with this bugged achievement., as I was tracking it very early during my gameplay.
After starting the Career Mode I noticed it went to 33% completed. I didn’t do any challenge or photography missions yet, and wondered what missions I completed in the career mode that could have pushed it to 33% (as I still didn’t get my PPL yet).
Then did the 3 Challenge missions, and the achievement progress went to 66%.
Then did 3 missions in Photography (first mission in each of the first 3 categories) getting a 3-star photo in each, but the achievement progress remained at 66%.
So it seems I got the first 33% from career mode although its stats indicate 0 missions completed, while after completing my photography missions I didn’t get the expected progress.