Just in case you have fallen victim of the confusion I see often in online communities, blogs, but also Microsoft official documentation: Dynamics 365 Business Central sandbox is not the same as Dynamics 365 Business Central preview. They are two different things. Keep in mind, in this blog post I am not talking about sandbox container environments (on-prem); I am only talking about online sandbox environments.
This is not pure semantics. Things in sandbox environments (and I mean, real sandbox environments of Business Central) differ from things in preview environments.