Is not not sensible really that in the UK we wait until the wind changes, at which time we can be sure the ash has cleared? Frankly I really don't like the idea of someone being on an ETOPS mission, an engine cutting out, and then spending however many hours looking out the window at that one remaining engine, crossing your fingers aware that it has been operating in and out of ash for several days. Isn't the whole point of ETOPS to remove any possible non-independent sources of failure? I don't see how engines operating in these conditions can be ETOPS certifiable, are they going to be doing full detailed inspections after every flight? If they're running normal schedules, impossible surely? I don't know, maybe the engineers can help here.
And a few more days shut down (wind changes fri/sat) is probably a lot cheaper than a fleet of wrecked planes. I actually think this is pretty much what will happen, the UK will stay shut, unless the volcano actually remains far less active, the airlines are somewhat less suicidal than some on here appear to be. Note BA appear to be accepting operations may not commence today without protest.
And please can people use a bit of nuance and try to understand the perfectly logical basis behind the UK being shut while other areas are open, it's not that difficult, but some are determined to ignore any evidence that doesn't support their position:
a) the UK is nearer Iceland than Continental Europe is
b) prevailing winds have been driving the ash cloud west when it gets to the north sea, so the densest part travels straight over SE England, avoiding the continent.
Is that so hard?