I am taking part in a mooting competition that constitutes a problem in offer and acceptance (contract law). What I am trying to prove is that the advertisement in the newspaper was an offer and not merely an invitiation to treat. I have three submissions, and the one I need to support with an authority is:

The respondents subsequent actions in placing notification in the newspaper that the goods were no longer available demonstrated that she intended the advertisement to be an offer which would be binding upon acceptance.

In short, if the respondent truely intended for the notice in the newspaper to amount to an invitiation to treat, then why did she see the need in publishing another notice THE NEXT DAY informing people that the goods were no longer available? (I know some may say public policy, to keep customers satisfied, prevent potential conflicts etc, but I need help in proving the contrary) Surely she knows that newspaper advertisements are only temporary anyway and that in a week or so her notice will be removed automatically.

So any authority or cases that could back me up? If not a strong argument?

Thank you