Although the layout and set-up of Sales Channels has remained relatively the same, the way they operate has changed. On V3, merchants are able to install multiple independent sales channels. However, orders will only be synced to and from the channel they were placed on, and products and orders can no longer be synced between sales channels.
For example: orders placed on each Sales Channel will sync to uAfrica, where the order can be fulfilled and shipped. Once fulfilled, uAfrica will update the order status and the inventory to the relevant Sales Channel.