The assignment is part of a new Coke policy to groom talented marketers for senior management positions.
Oades takes on the profit-and-loss remit of outgoing commercial director Paul Gordon, who becomes region manager for France, but will have additional responsibilities for brand building and business development.
"Marketing is the focus of our business and we are pursuing a policy of developing people who have marketing strengths into all-round managers," explained a spokeswoman for Coca-Cola GB.
Julia Goldin, consumer brands director, takes on Oades' marketing director role. She will have day-to-day responsibility for Coca-Cola's core brands, such as Coke, Diet Coke and Diet Coke with Lemon, and its youth brands Fanta, Sprite and Dr Pepper. She will also liaise with Coke's roster of advertising agencies for its £37m budget.
Both Oades and Goldin will report to Tom Long, Coke's divisional president for GB & Ireland.
Oades became Coke's British marketing head in the summer of 2000, having served as the company's division marketing director for Asia Pacific, in Australia.
She introduced the 'think local, act local' strategy, thought up by then chief executive Douglas Daft, who took the reins in 2000.
This involved a sweeping change in Coca-Cola's UK advertising arrangements, adding local hot shops such as Mother and Soul to Coke's more network-based roster, comprising McCann-Erickson and Wieden & Kennedy.
The strategy proved a success, with much acclaimed advertising. Mother continues to work on Lilt, Dr Pepper and Schweppes and was called in to consult on Coke Original this year. Soul still handles the fast-growing Fanta brand.
Oades has also been a strong advocate of using diversified media in contrast to Coke's previous focus on heavyweight TV advertising.
Smaller niche brands such as energy drink Burn and fruit drink Alive have been less successful.
More recently, Coke has muscled in on Pepsi's traditional dominance of pop music, and is planning a number of exclusive concerts.