Revocation of registration cancellation: limited late application window conditioned on return filing and payment of due tax and charges. Registered persons whose registrations were cancelled under clause (b) or (c) of sub section (2) of section 29 and who failed to apply within the original time limit may apply for revocation up to a prescribed final date, only after furnishing returns up to the effective cancellation date and paying tax, interest, penalty and late fee; no further extension will be available.