Information is needed regarding the content of the various license types
If a standard Workstation license and a Workstation Pro. license are purchased, and are loaded on to a License server, when is the professional license used?
The difference between the standard Workstation license and the Workstation Pro. license is that the professional license allows the usage of the editors (Graphics editor, Function Block editor, Script editor, Menta editor).
The licenses can be seen as a bundle of license features that can be checked in and checked out separately from each other.
When a workstation attempts to use any of these editors the license server is asked to check out the license feature for that editor and if successful, that feature is "taken" and cannot be used by any other Workstation until the first workstation leaves the editor.
This means that if you have one professional license, only one Workstation can use the same editor at the same time, if you e.g. have 2 professional licenses you can have 2 Workstations using the same editor at the same time. However, any Workstation can use any editor as long as there is a free license feature for it on the license server.