What study system works best for the EA exam when I need to turn review materials into passing performance quickly?

A real Reddit thread titled 'Erroneous underpayment of estimated tax penalties on trusts' raised an EA exam or tax-practice issue that deserves a clearer framework than a typical forum reply. I want the exam-ready or practice-ready version using the actual source signal rather than generic advice. Source context: I have four different trust returns where either: * they elected to file as an estate, and the tax year ended less than two years from the date of death, or * they filed a trust return for the prior year showing no tax liability. In all cases, estimated tax payments were not required, but the IRS is sending out erroneo