The phone call never came… but the email did on July 20, 2018. It said that Migraciones was ready to make me a Peruvian citizen and that I should contact them when I returned to Peru (I was visiting family in Minnesota). So, I did. (In all fairness, it is possible that they called but I could not receive the call when I was out of the country.)
Today, I contacted Migraciones and was told that my name would be added for the next ceremony. The ceremonies usually happen Tuesdays or Wednesdays at 10:00 AM. In the next few days (after Fiestas Patrias here in Peru) I will receive an email with all of the details.
I await the next step.