The guide outlines the recommended procedures for upgrading Elastic App Search to ensure access to new features, security enhancements, and performance improvements while minimizing disruptions in production environments. It emphasizes the importance of testing upgrades in a development environment and backing up data using Elasticsearch snapshots to safeguard against data loss. The document describes three primary upgrade methods: simple in-place upgrades with downtime, snapshot-based upgrades without downtime but requiring client-side changes, and in-place upgrades in read-only mode for App Search version 7.6 and later, which do not require new infrastructure or client configuration changes but make rollback more challenging. The choice of method depends on factors such as deployment mode, resource availability, and tolerance for service downtime. For Elastic Cloud users, the guide suggests either a default in-place upgrade with downtime or a snapshot-based process for uninterrupted service. Additionally, it highlights the importance of troubleshooting potential upgrade failures by checking application logs and suggests filing a support case with Elastic if issues persist.