I seriously doubt that this is different in BrE compared to AmE. Here's the usage note from my American Heritage Dictionary: ... People (not persons) is the proper term when referring to a large group of individuals collectively and indefinitely: People can be pushed only so far.
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... People (not persons) is the proper term when referring to a large group of individuals collectively and indefinitely: People can be pushed only so far. Persons is applicable to a specific and relatively small number: Ten