Woody, good to hear I'm not alone (again), but it's not good it's happened.
I also couldn't access sites using coms dns, so switched to google dns as a temporary workaround (I even rebooted the router first to be sure it wasn't a glitch at my end - I don't think I've rebooted my router so much in such a short space of time!)
Anyway, I raised a ticket at about 07:50, and 50 minutes later got this response:
"Please be advised that i have check your account and run line test that come with no fault on line. Also i have reset the Data Port, could you please remove google public, test the line and advise with results?"
No admittance of any dns issues, or any investigation into possibility of dns issues at their end. I won't be able to retest until tonight when I get back home.
Also, because the port got reset my connection died again, but not knowing what was going on I ended up rebooting the router again to see if that resolved it - and because it worked after that I was beginning to think my kit was faulty...
And to be fair to coms, if they had sent you an email you probably wouldn't have received it - so they were just optimising the process by not sending one in the first place