Additions and changes to the Twilio platform
Beginning March 16, 2022, for new customers only, Twilio SendGrid will begin limiting category statistics on a seven-day rolling basis. This means all categories will be available for the first seven days. After seven days, the top 100 categories will be retained for free customers, and the top 1,000 will be retained for paying customers.
Customers who require access to all category statistics can use the Event Webhook to retrieve and retain the data on their own systems as long as they save it within seven days of first sending the event.
Twilio SendGrid accounts created before March 16, 2022 will continue to have access to all category statistics during this phase of our changes to the category statistics system. Limitations for existing customers are planned to begin in Q2 2022.
Many customers find that Unique Arguments, which are not limited, are the best solution for their needs. See the "Categories vs Unique Arguments: Benefits & Limitations" blog post to better understand these two tracking tools.