This article is basically a PSA that if you have any codes that are redeemable via Club Nintendo will expire on August 1. This includes both Wii U eShop and 3DS eshop.
This comes after the news broke last month that Nintendo would be shutting down on this day. If you have any physical rewards, those will continue to be shipped out until the end of September.
A successor to Club Nintendo has not been revealed at this time, but there is one currently in development as Nintendo is working with DeNA on this upcoming membership service.