Portrait Foundation - Deployment 'requires downtime' message

Product Feature: Configuration suite
The warning message in the screen shot below is sometimes shown before an deployment is activated. It is part of the Live Updates deployment framework - details of which are covered in the product documentation of the same name.

User-added image

Specifically, to determine whether the warning needs to be shown, a stored procedure called p_amc_adm_get_req_downtime is run from the code, passing in the old and new Deployment Ids.
Currently, the only test within the procedure is to check whether there have been any changes in either the 'Search' or 'Unique' tables for any Configurable Business Entity (CBE) definitions. These tables have to be consistent with the latest active deployment, rather than earlier versions. Existing sessions will continue to use the old Deployment Id, but they would still use the latest Search and Unique tables - which could result in a mismatch.
Therefore, if changes have been made to any of these tables as a result of a configuration change, this warning is given during deployment, to inform the administrator that users with existing sessions would need to be updated before they fully work as expected.
UPDATED:  April 3, 2017