Revised return from itr4 to itr3

A friend mistakenly filed an ITR 4 without declaring F&O transactions, which now necessitates a tax audit. The query explores the possibility of filing a revised ITR 3 and the implications of not having filed the required Form 3CB-3CD. The advice suggests that a revision might not be possible, and while penalties for a missed audit report are uncommon, a notice under Section 148 could be issued later, requiring the filing of a correct return with applicable tax and interest.