Abstract
The precursor phase of the outburst started in October 2008 was intensively monitored by photometry, high-resolution optical and near-IR spectroscopy and interferometry. Contrary to the expected monotonic outburst a long precursor phase with cyclic smaller outbursts was observed. A more distant part of the circumstellar disk, where Brγ is typically formed was significantly affected only in January 2009. Consequently, our 2008 AMBER observations enable to derive geometrical and physical parameters of the disk formed during previous outbursts, but the new inner disk visible in the optical emission metallic lines could not be spatially resolved.
