I am not a lawyer, but I have led several offers of this kind in an old role.
Jake is correct in the assessment. In brief, the bid can be extended at any time for a period of up to 12 months. In practice, a bid for greater than 3 or 4 months is unusual. If the bid is unsuccessful, it may just close, but most offers do get to a conclusion.
If the bidder changes the terms of the offer (higher bid or another change) then there is an automatic 7-day extension. Same when the bidder gets to 50%.
Happy to assist in this and I hope that helps.
AL
NWE Price at posting:
6.8¢ Sentiment: Buy Disclosure: Held