Because this is a limited-time promotional offer, you will not be able to keep the $15/month rate if you make changes to your plan during the 3-month promotional period. This means if you purchase a lower data plan and then decide during the promotion that you want to increase your data, you will have to pay the difference between the promotional price and the standard rate of the new plan.
That’s why we recommend just buying the Unlimited plan for $15 a month to start. It’s the best deal.
Then after 3 months you should know how many GBs per month you really need. You can lower your data amount when you renew by logging into the Mint Mobile app or your account at mintmobile.com/login.