(1) In case any modification is made to the bidding documents or any clarification is issued which materially affects the terms contained in the bidding documents, the procuring entity shall publish such modification or clarification in the same manner as the publication of the initial bidding documents.
(2) In case a clarification or modification is issued to the bidding documents, the procuring entity may, prior to the last date for submission of bids, extend such time limit in order to allow the bidders sufficient time to take into account the clarification or modification, as the case may be, while submitting their bids.
(3) Any bidder who has submitted his bid in response to the original invitation shall have the opportunity to modify or resubmit it, as the case may be, within the period of time originally allotted or such extended time as may be allowed for submission of bids, when changes are made to the bidding documents by the procuring entity:
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Provided that the bid last submitted or the bid as modified by the bidder shall be considered for evaluation.