Everyone - if you're wanting to get your time display functioning before TomTom decide to fix it, or wait until sometime in August when the sat navs 'should' start showing the time again, please follow these simple instructions...
This works fine for my Carminat on a 2010 Renault Megane. Software version 8.843.
Go to the following link, and download the file. I didn't create it, it's not my work!
drive.google.com
Extract it so you see all the files in that one folder.
Eject your original SD card from your cars' Tom Tom device.
Place your original SD card in a card reader on your PC / Laptop. Copy the contents to a new folder, naming it something like Copy of Original TomTom SD card files... If you have a spare SD card, copy those files onto it.
Go back to the folder you have which contains the extracted files from the Google Drive Zip file that you have downloaded.
Copy the extracted contents of that downloaded folder directly onto either the SD Card from your TomTom, or into the folder of your new SD Card. Overwrite if asked to.
Place your SD Card in your TomTom device, switch on the device, and wait for the egg timer to go out...
After a few seconds or so, you'll be up and running again!