Ann: Iberdrola Achieves Change of Control, page-14

You will hold shares in a company that will no longer be listed on the ASX, therefore have no active market to determine price or be able to easily sell your shares into.
There is limited to no transparency other than the periodic reports the company will give you, and they can completely change the nature and structure of the business and its assets and if its not for the better your largely stuck holding what you have. In most cases the company will buy back your holding, but at what price is the question and often there is very little premium or multiple offered over the accounting value.

If they end up reaching compulsory acquisition status, you will get paid the offer price for your shares. They wont amend the offer to achieve a larger % of the company, some previous posters don't seem to understand the legalities of takeovers.