Regulation 52 defines the rules that are to be followed by contracting authorities wishing to advertise notices (contract and PINs) at the national level. The main objective of this article is to ensure that while contracting authorities can publish these notices, they cannot do so before publishing them on the Official Journal. The logic is self-evident: without this rule, contracting authorities would be free to advertise nationally earlier (or with more information) than at European Level, thus disadvantaging suppliers based in other Member States.
It is noteworthy to mention as well that the Regulation refers to the "buyer profile" on the internet and not, as it would be expected, the procurement portals from the various Governments (ContractsFinder, Sell2Wales, Scottish Procurement Portal). Sincerely, I do not understand why this was not mentioned here, particularly when the Westminster Government is trying to get contracting authorities to advertise contracts below-thresholds on ContractsFinder.