Release wave
Microsoft's twice-yearly platform update cadence for Dynamics 365 — Wave 1 in April, Wave 2 in October, with preview, GA, and mandatory upgrade phases.
A release wave is Microsoft's twice-yearly major update for Dynamics 365 and the Power Platform — Wave 1 in April, Wave 2 in October. Each wave delivers new application features, new platform capabilities, performance improvements, and deprecations. The wave lifecycle includes a preview build available roughly six weeks before general availability, allowing customers to test in sandbox; general availability rolls out across the tenant base; mandatory upgrade completes the rollout by a published cut-off date. Customers configure an update window (a permitted offline span) for the upgrade to apply. Extensions on AppSource are pre-tested for compatibility; per-tenant extensions need customer / partner recompilation. Monthly hotfixes ship between waves.