When you cancel your account, it will continue to act as a pre-paid account until your usage/billing period is over. Once your usage/billing period ends, the account will automatically downgrade to the free Hobby plan. The Hobby plan has a very limited usage allowance, as it is intended for personal or testing use. Receiving emails about your account exceeding its usage limits could be a result of being over in the following categories: CalendarsCalendar subscribersDomainsAccount usersThe above categories are considered "ongoing usage." Unless the additional ongoing usage is removed from the account, you will receive transactional emails that your account exceeds its u...