Composition levy effective date: option activates from financial year start or appointed day, subject to registration requirements. The composition levy option's effectiveness depends on how intimation is filed: if filed via the delayed route, effectiveness is from the beginning of the financial year; if filed via the standard route, it is from the appointed day. Intimations filed through the intermediate route take effect only after registration is granted, and the option then becomes effective from the date fixed under the rule governing date fixation for post-registration applicants.