Wow, I hadn't even thought of DNS issues because I was first made aware of the strange errors at the same time I had made changes to the DD code. The DNS server would have changed about 5 or so days prior to that. So of course, I went off down the path of something I had changed in the code had broken it all and didn't consider the obvious.
The obvious being, as I'd explained to a friend the other day, if it works for some and not for others - and even then sometimes it works for everyone - suspect the DNS!
I've updated the DNS server (it was wrong, thanks DancingStar's IT dude) and things should return to normal over the next few days. DancingStar - you'll need (in a few days) to ask your IT dude to remove the entry from the hosts file again so that when we do manage to move the server later in the move/early next month, you're not left wondering where we went again :-)
Thanks for your patience everyone!
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