Multiple versions of customisations in separate tenants can cause inconsistent behaviour and performance issues.
Without careful management, it's possible to have different versions of customisations active on different tenants. Conflicts between customisation versions can have unpredictable effects, including errors and performance decreases.
To optimise site performance and consistency, we recommend maintaining customisations in only a single tenant (ideally tenant 3).
Customisations at the database level
While MYOB Acumatica is a multi-tenant environment, there are certain elements of a customisation that apply to the database only, and not the website. For mor information, see Publication of Customisations in a Multi-Tenant Environment.