blocking attachment download outside the corporate network(OWA)

Hi all

I can see we can use OWAMailboxPolicy management and setDirectFileAccessOnPublicComputersEnabled $False <o:p></o:p>

but if a user selects “private computer” does this bypass the above setting?

Or

Is there something clever under the hood that recognises the IP address of the computer/device and defers to this setting?

many thanks