For new subscriptions, as well as one-time orders, Ka'Chava bottle can be added post-purchase. Once you pay for your shakes, a page will load where you can choose to add Ka'Chava Bars to your order, and then after you choose whether to add bars or not, a page will load where you can select bottle(s) to add to your order.
Existing subscribers are able to add Ka'Chava bottle(s) to their next subscription order from from their accounts.