We will charge you the difference between the current and new packages if you upgrade your subscription. In addition, we give credit for the difference. i.e., If you’re on the 58plan(6Kcredits)andupgradedtothe145 plan (15K credits), we’ll charge you 87(Pricedifference)andadd9Kcredits(creditdifference),andwewillmoveyoutothenewsubscriptionsoyournextbillisonthe145 plan.