Microsoft has announced that it is increasing the recipient rate limit with the Office 365 P1 plan to allow users to send email to up to 1,500 recipients per day. This is an increase from the previous limit of 500. Here’s the announcement:
You’ll also find information about Bulk Email and Daily recipient limits here:
Not unexpected and shows that Microsoft is listening to its customers and adjust things as required and with Office 365 they can do this very quickly.