Line profiles of the Sr ii 4215.5 Å line around rotation phase 0.68 for all available data sets between 2002 and 2010. The thick red continuous line refers to observations with SOFIN in 2010, the blue continuous line to those with UVES in 2005, the dashed line corresponds to observations at the Thüringer Landessternwarte and STELLA, and the dotted line corresponds to observations with SOFIN in 2002.