Sprint on Tuesday announced a new “loyalty service credit” for existing customers who want to keep their rate plans and still get new iPhones.

The credit applies to those who opt for a relatively new option that allows customers to lease an iPhone 6 for two years. With the “loyalty service credit,” existing customers can lease an iPhone 6 for $5 per month, rather than $20 per month.

Great offer, right? Not exactly.

The problem is, for most existing customers, that’s actually no deal at all. They would be better off paying $20 per month for the leased iPhone and taking advantage of Sprint’s $50 per month iPhone plan, which includes unlimited data, talk and texting.

So why is Sprint doing this?

A Sprint representative said some customers don’t want to change plans. Or, maybe once they talk to an in-store rep, they will decide they do want the new option.

Sprint came under fire for initially offering lower rates only to new customers, but this offer seems unlikely to win hearts. It’s doubly odd, since Sprint already is offering them a pretty good deal.

The current lease offer, which applies to new and existing customers, offers the option to get a new iPhone 6 for no money down and pay $70 per month for an iPhone 6 and unlimited data ($20 for the iPhone lease and $50 for unlimited service). The only big catch is that customers are leasing the iPhone, meaning that at the end of two years, the phone goes back to Sprint.

But if you still want that “loyalty service credit,” the offer starts Monday and runs through Jan. 15.