(1) As soon as practicable after a referral has been made under section 15M, the adjudication officer shall, subject to subsection (3), give the undertaking or association of undertakings-

(a) a copy of this section,

(b) in respect of a referral under section 15M(2), a written notice stating that the undertaking or association of undertakings may make submissions in writing to the adjudication officer on the full investigation report prepared under section 15L within the period of 30 working days from the date the undertaking or association of undertakings receives the notice, or such further period, not exceeding 15 working days, as the adjudication officer may allow, and