Schema field promotion changes do not take effect until the BizTalk Server Application Service is restarted

After you modify a deployed schema and then re-deploy the schema, changes to the schema do not take effect and field promotion changes are not seen.

The Microsoft BizTalk Server Application Service must be stopped and then restarted after the modified schema is redeployed.

This behavior is by design.

When a deployed schema is redeployed, any changes in the assembly of the schema are promulgated to the Global Assembly Cache (GAC). The updated assembly is loaded into the default application domain (AppDomain) from the GAC. If the assembly already exists in the default AppDomain, the assembly in the AppDomain is not updated until the AppDomain is recycled by restarting the BizTalk Server Application Service.