Upper panel: an example of a discrepant transit. The green points are for the data taken at the Cassini telescope (this work) through a Gunn r filter. Lower panel: an example of the consistency of followup observations made on the same date of 2011/10/05 by different observers. Lighter blue dots are for the data taken at the Cassini telescope (this work), whereas the red ones for those taken at CAHA 1.23 m (this work). Some of the difference in depth between the two datasets is due to different filters used, Gunn i and Johnson R, respectively. The vertical line represents the expected transit minimum time.