The most helpful course is the ACP 100 certification prep course: https://training.atlassian.com/course/acp-100-certification-prep-course
Go through it thoroughly and pay attention to each and every topic discussed in this course especially on functionalities you work with less often .
In addition to this,
As part of an ongoing series, Atlassian University is offering this free webinar to strengthen your Atlassian product skills and learn directly from Atlassian experts. @Steve Byrnes&nbs...
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