Review concludes after an eight-month competitive process.
Employees being informed this week about roles at risk of redundancy.
Grey will split from AKQA as part of the move.
Campaign charts the WPP media arm's history amid ongoing change under global chief executive Brian Lesser.
WPP media arm to change name as part of ongoing restructure.
A small number of agencies have embraced the four-day working week, and while agency leaders seem to be up for it, there are a few hurdles to overcome before it can become a more general reality.
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