Got the answer from Blackmagic support today. I guess they never bother responding to these posts.
What you have to do is connect your Hyperdeck to your computer (via usb) and change any setting in the Hyperdeck Setup software and save the settings. You have to have at least version 4.4 of Hyperdeck Setup.
This will update the internal clock of the Hyperdeck to sync with your computer's date and time.
I just tried it and it worked for me.