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Planets form during the time comma when the central star accretes material from the surrounding circumstellar disk and the final system architecture depends on the poorly known accretion and ejection history. Accretion tracers are particularly prominent in the UV so that the HST legacy program ULLYSES was conceived to obtain a UV atlas of accreting comma young stars. In the UV comma however comma extinction is a severe issue and already moderate amounts of dust can completely extinguish any (accretion) signal. Accretion and extinction decline with age so that it is imperative to understand how well UV observations actually trace genuine accretion emission for higher absorption column densities or if rather other processes comma namely jet emission or light scattered towards the observer by the upper disk layers comma mimic accretion in spatially unresolved data such as the ULLYSES COS observations. Our target comma the classical T Tauri star AA Tau comma currently experiences a long-lasting dimming event comma presumably caused by inner disk dust comma i.e. comma the star is currently hidden behind a d_commanatural coronographd_comma and the direct emission is greatly reduced. Spatially unresolved HST COS data suggest that jet emission and scattering dominate the integrated FUV light during the dimming event. We propose to utilize this situation to detect UV scattering for the first time and to measure the jet.s contribution to the FUV light through spatially resolving the emission with a series of STIS long-slit spectra. This experiment comma right in time for ULLYSES comma will uncover what fundamentally limits UV accretion studies comma lack of signal due to absorption or d_commacontaminatingd_comma emission spoiling the interpretation of the signals.