I have a question about the categories in SendGrid, about their 7-day rolling basis. Base on the SendGrid docs, they said:
"For example, if you send with a total of 2,000 unique categories on February 1, you will be able to access the stats for all 2,000 categories from February 1 through February 7. On February 8, if you attempt to retrieve the category stats for February 1, only the top 100 (free plans) or top 1000 (paid plans) will be available. On February 9, categories in excess of the limit will be trimmed from February 2, and so on."
So if in February 1 I sent less than 1000 unique categories (100 categories), so that means they will not be deleted following on the 7-day rolling basis in 8 February? And those 100 categories still exist after 8 February?