What is the validity period of the Registration certificate issued to a Casual Taxable Person and non- Resident Taxable person?

In terms of Section 27(1) read with proviso thereto, the certificate of registration issued to a “casual taxable person” or a “non-resident taxable person” shall be valid for a period specified in the application for registration or ninety days from the effective date of registration, whichever is earlier. However, the proper officer, at the request of the said taxable person, may extend the validity of the aforesaid period of ninety days by a further period not exceeding ninety days.