I read from CDF but the link to that german site is no longer there

http://www.china-defense.com/smf/index.php?topic=239.msg274467;boardseen#new

This June2015 news says 9 yrs delay:https://news.usni.org/2015/06/24/indian-attack-submarine-to-conduct-final-trials-after-9-years-in-yard-for-upgrades

Janes said it was a 14yrs delay

http://www.janes.com/article/56586/india-s-cag-lambasts-long-delayed-kilo-refit