Offer period limitation: collective investment schemes limited to a short initial subscription window with a conditioned extension. Regulation 30 caps the initial offer period for a collective investment scheme at fifteen days. The offer may be extended for a further maximum of fifteen days only if the Collective Investment Management Company issues a public notice before the initial fifteen-day period expires. This limitation reflects amendments to the SEBI (Collective Investment Schemes) Regulations that reduced the permissible subscription duration.