Refeer this topic:

Eligibility Requirements To be eligible for an upgrade, you must:

have successfully completed all Tech Provider Get Started steps greater than or equal to 2500 average daily conversations (the average daily number of conversations on the WhatsApp Business Platform between you and your business customers over the last 7 days) 10 or more active business customers (have used your app to send at least 1 message in the last 30 days) maintain a business phone number quality rating of 90% or better/

have successfully completed all Tech Provider Get Started steps greater than or equal to 2500 average daily conversations (the average daily number of conversations on the WhatsApp Business Platform between you and your business customers over the last 7 days)

That would be, the conversations of customers that integrate into my app with their end customers?