Your database HEROKU_POSTGRESQL_SILVER_URL on datacustodian-dev requires maintenance. During this period, your database will become read-only. Once maintenance has completed, your database credentials and hostname will have changed, but we will update your app's config variables accordingly to reflect the new database connection string.
This automated maintenance is a necessary part of our Hobby tier plans, Dev and Basic. Should you need more control over maintenance windows, a production database (Standard tier or higher) offers more control over database maintenance, as we are able to schedule them in advance and provide better tools for self-served maintenance.
We expect maintenance to last just a few moments depending on the size of your database. We will notify you when maintenance begins, and again once it's complete.