Thanks for the swift feedback. Tried again this evening and it's working. Super Hub log shows it started working on its own at 14:53 this afternoon.
BTW superhub logs specifically shows it coming back online at 13:51GMT (13:51BST). Oddly, it had reset to factory defaults in the process, and changed the password back to the default.
Mon Apr 09 13:51:54 2012 Warning (5) Lost MDD Timeout;CM-MAC=a0:21:b7:34:04:11;CMTS-MAC=00:11:bc:a8:50:44;CM-QOS=1.0;CM-VER=3.0;
Mon Apr 09 13:51:54 2012 Warning (5) MDD message timeout;CM-MAC=a0:21:b7:34:04:11;CMTS-MAC=00:11:bc:a8:50:44;CM-QOS=1.0;CM-VER=3.0;
Mon Apr 09 13:51:47 2012 Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=a0:21:b7:34:04:11;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0;
Mon Apr 09 13:51:28 2012 Critical (3) SYNC Timing Synchronization failure - Failed to acquire FEC framing;CM-MAC=a0:21:b7:34:04:11;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0;
Mon Apr 09 13:49:40 2012 Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=a0:21:b7:34:04:11;CMTS-MAC=00:11:bc:a8:50:44;CM-QOS=1.0;CM-VER=3.0;
Mon Apr 09 13:49:24 2012 Critical (3) SYNC Timing Synchronization failure - Failed to acquire FEC framing;CM-MAC=a0:21:b7:34:04:11;CMTS-MAC=00:11:bc:a8:50:44;CM-QOS=1.0;CM-VER=3.0;
Mon Apr 09 13:48:20 2012 Critical (3) DHCP FAILED - Discover sent, no offer received;CM-MAC=a0:21:b7:34:04:11;CMTS-MAC=00:11:bc:a8:50:44;CM-QOS=1.0;CM-VER=3.0;
Mon Apr 09 13:38:10 2012 Critical (3) Ranging Request Retries exhausted;CM-MAC=a0:21:b7:34:04:11;CMTS-MAC=00:11:bc:a8:50:44;CM-QOS=1.0;CM-VER=3.0;
Mon Apr 09 10:15:42 2012 Critical (3) DHCP FAILED - Requested Info not supported.;CM-MAC=a0:21:b7:34:04:11;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0;