AT&T is offering a discount to customers who want to get a new iPhone before their contracts are up. When AT&T customers head over to their accounts on Monday, they’ll find the option to upgrade to an iPhone for a discount. On the 16GB, 32GB, and 64GB iPhone models, customers will receive $200 off the unsubsidized price. On the 16GB option, for example, customers who would normally pay $650 for an unsubsidized iPhone 5 can now pay $450. The 32GB and 64GB models are more expensive by $100 and $200, respectively. It’s not clear why AT&T is offering the reduced pricing, but it could be an attempt to keep customers buying iPhones as anticipation grows for the iPhone 5S. That device, which is expected to launch sometime this year, will replace the current iPhone 5 as Apple’s flagship handset.