How often can I change my Verizon plan ? The only thing that I liked on ATT was the rollover feature . My month-to-month minute usage varies widely , last month I had hundreds of minutes left and this month already reached the limit with two more weeks to go . If I change my plan now to unlimited , will it take effect immediately or I will have unlimited minutes only after 2 weeks when my current billing cycle ends? And at the end of the month can I switch back ? How often can I do this ?