According to the provisions of SEBI guidelines and the historical timelines of the Companies Act, a company must secure its minimum subscription within how many days from the date of opening the issue?

Under Section 39(1) of the Companies Act, 2013, read along with regulatory SEBI corporate rules, if a company does not receive its minimum subscription (typically $90\%$ of the issued amount) within 120 days from the initial prospectus opening date, the entire application amount received must be fully refunded to the investors.