Confirmed this at fencing by borrowing Neil's phone and swapping SIMs between his Samsung and the Z1010 and 6680. Sure enough, the fault followed the SIM. Neil, Antony and April seemed inordinately amused by my having multiple phones. Surely that can't be that unusual these days? Most people must have been through at least one upgrade by now...
Anyway, fencing itself proved a good night. Hell, even managed to beat Antony for once. Graham even asked if I'd been secretly training. Good sign, I guess.
Got home and called Orange again. What a bunch of tossers. The guy was a tad hard of thinking, took a while to grasp the chain of reasoning: fault follows SIM between phones in multiple locations, other SIM in my phones works OK -> SIM is Donald Duck'ed and then needed to be prompted to add this to my incident note. Even after he accepted the diagnosis, it seems once an incident has been referred to technical support, he can't override it and it may take up to 3 days for tech support to even acknowledge it! Was barely civil by the time I ended the call.
Today, contacted an ex-colleague who's now at Orange who said she could have a word with head of call centre. In the meantime, I have got myself a temporary PAYG SIM. Number available on request. Just as well this can be expensed... God, I feel naked without my usual mobile connection.
While I was out sorting this out, also paid US visa fee and got photo taken so I guess I'm all set for the interview.