Deploying during a Salesforce Seasonal Release (Spring, Summer, or Winter) 1introduces technical risk. If a2 sandbox is on a different version than production, a consultant might build a feature that works in the sandbox but fails in production due to a change in the underlying platform logic.

Two Critical Steps for Alignment:

Review Sandbox Preview Instructions (A): Every release has a "Preview Window." Salesforce provides specific instructions on how to ensure at least one of your sandboxes is upgraded to the next release before production. This allows the consultant to perform Regression Testing—checking that the custom nonprofit features still work perfectly on the new version of Salesforce.

Verify Release Matching (D): Before a final deployment, it is a best practice to ensure the Sandbox and Production are on the same release version. If production is still on "Winter '25" but the sandbox has been upgraded to "Spring '26," you are testing in an environment that doesn't match the live system. Alignment ensures "What You See Is What You Get."

Why other options are incorrect:

Support Case (Option B): Salesforce generally does not allow you to "change the version" of a release for a specific org via a support case; you must follow the standard release schedule and sandbox refresh rules.

Change Set Timing (Option C): You should avoid deploying a Change Set during the upgrade window itself, as the production instance may be intermittently unavailable or undergoing its own internal schema updates, leading to deployment failures.