If upon the date fixed for delivery in accordance with subsection 15b(f) of the Act cotton class certificates shall not have been issued by a Marketing Services Office for cotton to be delivered pursuant to such notice, samples of which cotton shall have been in the custody of the Marketing Services Office for the time hereinafter prescribed, the delivery of such cotton may be made upon compliance with and subject to the conditions specified in §§ 27.52 through 27.55. Sections 27.52 through 27.55 shall not apply to cotton upon which a Marketing Services Office has already issued cotton class certificates pursuant to this subpart.