I seem to remember reading that during certain times, all stops operate
by request, but I can't find such information on TfL's Buses site.

But on my recent visit to London, I was observing buses at a compulsory
stop in Holborn - all Arriva buses simply sailed past the stop (yes,
those buses *Do* stop there), and all (former) Stagecoach buses did stop.

Are all stops now request stops 24Hr/day, or are some companies
enforcing the rules more strictly than others?
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