Why Promoter did not send any emails during the last 48 hours
Update: Heroku Support has lifted my account limit and all emails that were stuck in the queue have been sent out now.
Promoter relies on Mandrill for sending out transactional email. Reminders for festival deadlines, review copy requests from YouTubers, bulk sending of Steam Keys and press coverage notifications are all delivered through Mandrill. Yesterday, Mandrill announced a major change in their pricing structure and feature set and removed the option to provision, upgrade or downgrade any Mandrill add-ons via Heroku. Promoter is using the paid Heroku add-on which has hard limits on how many emails you can send per month depending on your plan. Just before the end of my billing period, and at roughly the same time as the Mandrill announcement, my account hit the sending limit of my plan. Ironically Mandrill was unable to deliver me a transactional email about the fact that I'm running low on credits. (I double checked that I have alerts turned on for my account.)
This afternoon I realised that Mandrill had stopped sending out emails and queued them in its backlog until my billing period would reset, or until I upgraded my plan. However, since Mandrill removed provison of the Heroku add-on without any notice, I was unable to upgrade my plan. Instead I got an error message: “The plan you’re on no longer exists.” For Heroku users with a growing usage pattern, the 60 days migration notice Mandrill gave was effectively 0 days. Adding insult to injury, Mandrill does not even allow its Heroku users to migrate to their new setup until March 16, three weeks from now.
I was lucky to have a staging environment of my Heroku app that also had the Mandrill add-on installed, so I'm temporarily sending all emails from staging. However, around 1000 emails are still being held hostage by the Mandrill backlog, and I can’t do anything to get them sent out to my paying customers.
I'm deeply sorry that my customers were affected by this issue. I'm currently researching an email provider that can reliably deliver transactional email in the future.