An activist investment fund is to double its stake in G4S to 10 per cent, fuelling speculation it will push for a break-up of the security contractor, the Sunday Times said. Cevian Capital, a Scandinavian fund chaired by former City Minister Lord Myners, is already G4S's second-biggest investor with 5.7%. Its business is taking stakes in companies and putting pressure on management for change. The news comes as new G4S boss Ashley Almanza prepares to unveil his plans at the half-year results on August 28th. He will seek to put G4S's botched Olympics security contract and other missteps behind it.Centrica is considering returning more cash to investors next year after it finishes its current 500 million pounds share buyback, the Sunday Telegraph said. It could fund a similar programme from earnings in the US. The British Gas owner's Chief Executive, Sam Laidlaw, told the paper: "We have got the headroom but we haven't made any firm decisions." But paying out cash to shareholder could cause trouble if British Gas increases prices this winter.Mark Carney, Governor of the Bank of England, will face down financial markets on interest rates in his first big speech on August 28th, the Sunday Telegraph and other papers said. Carney will tell business leaders in Nottingham they should expect interest rates to stay low for three years despite the economy recovering faster than expected. Markets have shunned Carney's "forward guidance" by pushing up government borrowing costs. BoE Chief Economist Charlie Bean said on August 24th that forward guidance was meant to reassure consumers and businesses about the BoE's policy even if market rates did rise.BBA Aviation is eyeing a merger with an American rival backed by the Dubai government. The FTSE 250 jet-servicing company is in talks with talks with Standard Aero about a £2.7bn merger, the Sunday Times reported. Standard Aero owner Dubai Aerospace could be handed a big stake in the enlarged business. On Friday, BBA's shares closed at 307.1p after a 60% rise over the last year. Dubai Aerospace is said to value Standard Aero at about £1.3bn. Advertising giant WPP will report solid growth at its half-year results on August 29th, boosted by a recovery in the UK, the Mail on Sunday said. City analysts expect turnover up by 2.4% and headline pre-tax profit up 8% to £508m at the global economic bellwether, the paper said.Leading investors in Kentz are prepared to approve the sale of the engineering and construction company if bidders are willing to pay £760m, the Sunday Times said. Amec, the FTSE 100 engineering consultant, offered between 565p and 580p on August 5th and Germany's M+W has also made an approach. Both were rejected. Shareholders said 650p was the kind of price they were after. Kentz's shares rose almost 20% in the week ending August 22nd, closing at 567p and valuing the company at £666m. "Shareholders will be very robust on pricing," one investor told the paper.Britain's competition watchdog is expected to tell Ryanair to sell all or part of its 29.8 per cent stake in Aer Lingus, the Sunday Times said. The Competition Commission could issue its ruling as soon as Tuesday, ending a six-year saga in which Ryanair has been thwarted in its attempts to buy Aer Lingus by Irish, UK and European authorities. The demand may finally end a six-year corporate saga in which Ryanair has tried to buy its rival several times, only to be rebuffed by the Irish, British and European authorities. However, Ryanair may appeal against the ruling, the paper said.Online bookmakers Bwin and 888 will report mixed fortunes at their half-year results, the Sunday Express reported. Citing City analysts, the paper said Bwin was on August 30th set to post a 30% fall in interim earnings to €62m (£53m) and a 20% fall in sales as poker sales flagged. 888, which posts first-half results on August 28th, is expected to post revenue up 7% to $200m (£128m) on increased casino and poker sales.Consumers are ramping up their borrowing as the economy recovers, the Sunday Express said. Applications for credit increased more than 400% at Hitachi Personal Finance in the first seven months of 2013, the paper said. The surge in confidence among 11,000 customers sampled compares with the same period last year.