D18 is the same as S18 (and will be the same for M19 and J19). Yes the lectures are up-to-date and yes the OpenTuition lectures together with the additional OpenTuition resources and essential ACCA resources (all are available at https://www.accaglobal.com/in/en/student/exam-support-resources/fundamentals-exams-study-resources/f8.html) will be sufficient with an Approved revision kit/question bank and at least one mock exam.