I don't have one, but here's how I understand it.

The card has two accounts, a prepaid Starbucks card and a regular Visa card. The Starbucks account is used for Starbucks purchases. When the prepaid account gets low, an automatic top-up is done from the Visa account. This top-up earns a 3% bonus, so $100 = $103 in your Starbucks account. Other purchases earn 1% for the Starbucks account.

The 30 days is the legally required time limit for them to respond, you should hear from them much sooner.