Nintendo is giving some Switch owners the option to trade in their recently purchased systems for the latest revision of the console that offers improved battery life. But the offer to upgrade to the latest model of the Nintendo Switch appears to be limited to customers who purchased the original version of the Switch on or after July 17, the same day Nintendo announced the system update.

News of the exchange program originated on Reddit, where user DarthMewtwo said, “Nintendo told me if you bought your Switch after July 17th 2019, they can exchange it for the new upgraded model for free.”

Another user backed up that claim, saying Nintendo told them it “will replace my unit bought about a week and a half ago with a revision unit. I need to send it in on my own dime, so shipping costs and insurance etc. will not be paid by Nintendo and no label will be provided. They sent me an email with a case # and shipping address. If I follow those instructions they will replace the unit.”

Polygon contacted Nintendo’s customer service department and verified those details with a representative. Customer service told us that customers will need to cover shipping and insurance costs, and that customers should transfer their purchases to the new system using a Nintendo Switch Online account. The exchange offer appears to be specific to customers in the U.S. and Canada. I was told that I could not exchange an older model for any limited edition versions of the Switch, just the two standard SKUs of the latest model with improved battery life.

It’s not clear how long Nintendo will offer exchanges, especially now that details about the offer are more widely publicized.

The revised Nintendo Switch with improved battery life is in stores now. For some tips on how to tell which model you’re getting, check out Polygon’s guide to the new model.