Which is better, Updated ITR or FAST-DS if a person fails to report foreign income?

Taxpayers, who realise they've failed to disclose foreign income, have two routes: file an Updated Income-tax Return (ITR-U) or use Foreign Assets of Small Taxpayers - Disclosure Scheme, 2026 (FAST-DS). Taxpayers may find ITR-U economical when tax has been deducted overseas. FAST-DS may be attractive when funds' source is fully accounted for, but asset was accidentally omitted from Schedule FA.