TL;DR: All monthly bandwidth limits for emails and files have been removed. Existing hourly limits still apply, and new daily limits have been added. The monthly sum of the new daily limits is significantly higher than the old monthly limits.
More details: When building an email service, one of the things we realised quickly early on is that you have to deal with abuse and resource limiting issues. If you don't set any limits, people will abuse your service.
Because we always regarded speed and reliability as highly important, when we first chose our data center, we picked a place with a great network (NYI), however that came with higher bandwidth costs, which meant that we had to put systems in place to track and limit users monthly bandwidth usage.
Additionally over time we added systems to track email sending and receiving in real time, and added hourly limits to stop mass mail floods or spam sending runs.
Since adding these limits, we've found that the short term limits have become more important to stop abuse, while the monthly limits have become less and less of an issue, and from today, we're now removing all monthly bandwidth quotas.
We are still implementing hourly quotas, and have also added daily quotas, though the sum of these daily quotas over a month is significantly higher than the previous monthly quotas and is a large increase for all users.
|Recv hourly||Sent hourly||Sent+recv hourly||Sent+recv daily|