1. Some footnotes have been editorially deleted, the numbering is as in the original. Editorial summaries of portions of the decision are in brackets. Editorial deletions of text are indicated by three dots.
2. Pursuant to our authority under rule 29.5(g) to restate or clarify "[a]t any time" the Ninth Circuit's certified question, we have substituted the word "terminate" for the Ninth Circuit's word "rescind" in the question certified to this court. The reason for the substitution is that the courts below and the parties discuss this action in terms of Pacific Bell's ability to terminate, or otherwise change, its policy, rather than "rescind" it as that term is legally defined. A contract rescission is a statutorily gov- erned event that extinguishes a contract as if it never existed. Rescission is effected by the parties' mutual consent or mistake, failure of consideration, illegality, or other public purpose. (Civ.Code, §§ 1688, 1689.) The word substitution best reflects the decisions below and does not in any way affect the parties' legal analysis.