i don't do mandarin but i do dutch ab initio and because i'm teaching myself, i've gone through the syllabus
if your teacher purely follows the course... in this case pamoja... then you'll reach b1 or low b2 CEFR by the time you graduate. Of course with extra study, supplementary material, extension work and immersing yourself in mandarin culture like tv and news, you'll go even higher.
By attempting mandarin B SL past exams you can further your level.
if you want a certification of your ability then attempt an external examination that isn't in the ib... as your i