Normally, I set loads of updates in advance - DrunkDuck Poop, for instance, has enough strips uploaded to last until November - but today (Sunday 19 July) neither of them updated, even though they were both scheduled to. Any ideas why?

Because the whole site went down on Friday. The time system was re-set.
The strips might go up a little later hopefully. If it doesn't at all even after waiting, you may have to re-do them, sorry

Ah, I see. Well, they're up now, so I guess the crisis was averted.

Same song verse. July 20 no update!

Ditto, no update for Star Trax.

My updatey thing still thinks it's July 19th though.

Plat has been told about it, hopefully it will be fixed soon. I'm guessing no one on their end (or at the server) noticed because it was a weekend.