measures which involved outsourcing internal divisions to external companies. O2's IT division was outsourced to IBM Ireland, while the Network Operations division was outsourced to BT Ireland (who also run the network operations for Three Ireland). The Network team outsource was limited to the Field Operations team along with some other support functions. The Network rollout team & Transmission team remained in-house to facilitate future network changes. It was more cost effective to retain these divisions in-house. Charitable activities In 2006 O2 chose Irish Autism Action as their charity of choice. The three-year deal involved sponsorship, creating awareness, using O2 staff to assist the charity and using technology developed by O2 to assist children affected by autism. In 2010, the company's charity of choice became Headstrong, a charity providing mental health support to young people. Sponsorship programmes Over the years, O2 entered into some very high-profile sponsorship arrangements. In 1998 the then ESAT Digifone committed its support to the Hurlers & Footballers of Cork. They remained sponsors of Cork GAA for ten years. Another high-profile sponsorship agreement was their association with the Irish Rugby Football Union and the Ireland national team, which has been continued by Three. Building on their rugby links with Shannon RFU, O2 joined forces with the top level of rugby in Ireland. They also sponsored the West Stand at Ireland's former home ground, Lansdowne Road. They were also the title sponsor of one of the country's most high-profile venue, "The O2", now renamed the "3Arena". They were title sponsor of the Aisling Foundation's Ability Awards. Chief executive Tony Hanway was Chief Executive of Telefónica Ireland from his appointment in September 2011 until March 2015. Hanway first joined Telefónica in Ireland in 2005 as Head of Customer Care, subsequently becoming Consumer Sales Director. Immediately prior to taking the role, Hanway headed up the Consumer division of Telefónica in the Czech Republic, managing a team of over 4000 people across the retail, online and customer care functions. Criticism In July 2004 the company admitted overcharging 71,000 customers following a review of its systems. The disclosure meant that 136,535 O2 subscribers - more than 10 per cent of its customer base - were overcharged. Analysis by the Sunday Independent in January 2006 showed the massive margins being earned by Vodafone and O2 in the country were costing Irish mobile phone users about €300m a year. If the mobile phone