Mulryan joined the Groupe 15 years ago.
Loon last helmed the role of managing director of Starcom and Spark Foundry in Singapore.
According to her LinkedIn, she previously worked at Leo Burnett and Arc Worldwide Malaysia from 2003 to 2007.
In his new position, Huang will oversee all media, digital, and commerce brands in China and will report to managing partner APAC and CEO of North Asia Jane Lin-Baden.
Meanwhile, as ad agency holding companies cut the number of M&A deals by more than half in 2019, private equity groups contributed 44% more in deal value globally.
It's been yet another year of significant mergers and acquisitions in the marketing, advertising and customer technology sphere.