When you are selecting a subscription plan, you could also add WhatsApp channels in the Additional Items.
WhatsApp Pending Channel is the WhatsApp channel you would like to add for your Stella account, so you could start the WABA Setup in Channels later.
WhatsApp Channel is the WhatsApp channel that has completed the WABA onboarding and deployed a WhatsApp server.
Since WhatsApp requires a dedicated server for each WhatsApp number. We will start and charge the monthly subscription (i.e. US$99) once you have completed the WABA onboarding and deployed the WhatsApp server. After the deployment, we will count it as a WhatsApp Channel instead of a pending one.
Please note that you will only able to edit the number of WhatsApp Pending Channel on the subscription page, the number of WhatsApp Channel included on the page is only for reference.
You could also refer to our documentation here for the steps by steps WABA setup.