Dynamics 365 Business Central: accessing Early Access Preview in online sandboxes.

Business Central 2026 Wave 1 introduces early access preview sandboxes for partners to test the next major release before general availability. Early previews sync weekly with the development build and auto-delete 30 days after release, with support limited to DE, GB, and US localizations.

Key points

Partners with sandbox licenses can create early access preview environments aligned with major release update periods
Preview environments auto-update every Sunday to the latest development build with no manual control possible
Only DE, GB, and US localizations are supported for early access preview at launch
Preview environments are automatically deleted 30 days after the version becomes generally available
Early access preview does not replace Docker containers as an alternative testing method

Quotes

“During the early access preview period, only tenants that use the Partner Sandbox license can create new sandbox environments on the early preview version.” (Clarifies that early access previews are restricted to partners with specific licensing, not all Business Central customers)
“Environments based on the early access preview version are automatically updated to the latest build of the preview version every Sunday.” (Explains the automatic update cadence partners must expect when using preview environments)
“Microsoft will delete preview environments 30 days after the preview version becomes generally available (GA).” (Sets a critical deadline for partners to migrate preview work to production before data loss)

Context

Features: Early Access Preview sandboxes, automatic weekly updates, environment auto-deletion, localization support (DE, GB, US)
Versions: 2026 Wave 1, v27, v28, v29

Source: Stefano Demiliani, community blog. Summary, key points and quotes are derived (CONTENT-NOTICE.md); read the original for the full text.