That all three machines are affected in the same way leads me to think that it's my ISP that's throwing the spanner into the works. (My next step will probably be to see what my ISP thinks of that hypothesis :-)

That sounds like the obvious conclusion to me, too. You could always check whether it is a caching issue (either at the ISP or elsewhere) by appending a query string to the URL. Or indeed by using an https URL if one is available for that resource.

Good luck with your investigations.

In reply to Re^3: [OT] HTTP downloads and caching by hippo
in thread [OT] HTTP downloads and caching by syphilis

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