I have a new Spark UFB installation and the HG659b modem came with "V100R001C227B022" firmware, which doesn't seem to be very recent.
The modem admin pages have a "Firmware Upgrade" entry, but it has a "Browse" button which leads to a local path.
There's no (obvious) information on the Spark website on from where the current / latest firmware image should be downloaded.
Ideas, please?