During 2006-2008 the "Ula" class was slated for modernisation. Most notably, new communication equipment (Link 11), new electronic warfare support measures and a periscope upgrade. In May 2008, a contract for new sonars was signed, with the first submarine to have new sonar 21 months after that, and the last 52 months later. Furthermore, Kongsberg was contracted in 2012 to upgrade the submarines' combat systems. The 2020 long-term defence plan envisages the "Ula" class being kept in service until replaced by the new Type 212CD submarines in around 2030.