Starting at 1am EST tomorrow (August 4th), the Postmark web app will be down while they migrate their Linode instances to a closer data center to improve latency. The API and SMTP servers will remain unaffected. This migration is part of their efforts to optimize their architecture, hosting the core sending engine in a dedicated Rackspace environment and moving Linode instances to Atlanta for reduced latency. Postmark plans to open up more of their API in the future, allowing users to create servers or add sender signatures, but this update will not impact the current functionality.