Substitute service personnel who joined after the third cohort are unfortunate. The salary they were promised is completely different from the original terms, and the commitments made at the time should be taken for reference only. Personally, I am very satisfied with the work content and am able to participate substantially in R&D design. There are many experts in the unit who are willing to provide guidance, but not everyone is this lucky. As usual, there is also administrative work to do (for example, procurement cases), which may take nearly as much time as your main duties.