64.—(1) When fixing the time limits for the receipt of tenders and requests to participate, a utility must take account of the complexity of the contract and the time required for drawing up tenders, without prejudice to the minimum time limits set out in regulations 43 to 47.
(2) Where tenders can be made only after a visit to the site or after on-the-spot inspection of the documents supporting the procurement documents, the time limits for the receipt of tenders, which shall be longer than the minimum time limits set out in regulations 43 to 47, must be fixed so that all economic operators concerned may be aware of all the information needed to produce tenders.
(3) A utility must extend the time limits for the receipt of tenders, so that all economic operators concerned may be aware of all the information needed to produce tenders, where—
(a)for whatever reason, additional information, although requested by the economic operator in good time, is not supplied at the latest 6 days before the time limit fixed for the receipt of tenders; or
(b)significant changes are made to the procurement documents.
(4) In the case of an accelerated open procedure, the period mentioned in paragraph (3)(a) shall be 4 days.
(5) The length of the extension given pursuant to paragraph (3) must be proportionate to the importance of the information or change.
(6) A utility is not required to extend the time limit where—
(a)additional information has not been requested in good time; or
(b)the additional information requested is of insignificant importance with a view to preparing responsive tenders.