I am building a business where I want the infrastructure to be able to handle up to 30000 emails per minute during peak periods. The question is what kinds of services offer this? I expect to download the emails using SMTP or similar. I expect each email to have a total attachment size of 2 mb, and might have several attachments.
I have considered utilizing Parse API from SendGrid, but I am worried because they offer this service for free. I have contacted them and I am waiting for answer. Are there any better and more suitable alternatives?