The trading obligation referred to in Article 28 of Regulation (EU) No 600/2014 shall, for each category of counterparties referred to in Article 3 of Delegated Regulation (EU) 2015/2205 and Article 3 of Delegated Regulation (EU) 2016/592, take effect from the later of the following dates:
(a)((a)) 3 January 2018;
(b)((b)) the date referred to in Article 3 of Delegated Regulation (EU) 2015/2205 or Article 3 of Delegated Regulation (EU) 2016/592 for that category of counterparties.