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Early comma ultraviolet (UV) observations of hydrogen rich Type IIP-L core-collapse supernovae (CCSNe) are critical for understanding the connection between massive red supergiant (RSG) stars comma their mass loss comma and the subsequent SN explosion. During the RSG phase comma a significant amount of mass loss occurs comma and depending on the duration can surround the star with dense and extended circumstellar material (CSM). When the star eventually explodes as a CCSN comma high energy photons from the shock breakout ionizes the CSM. These ionization features can be used to constrain the properties of the CSM comma including metallicity density comma and structure comma mapping the evolution of the final years of life of the progenitor star. UV observations during the first two weeks after explosion are crucial for detecting these high ionization lines comma and are the most sensitive to lower densities and weaker CSM interactions which may occur in lower mass RSG progenitors. The dearth of UV (particularly FUV) observations of Type IIP-L SNe at this phase has left many open-ended questions about the role CSM interaction plays in d_commanormald_comma Type II SNe comma and a disruptive ToO with HST in the UV is crucial to obtaining these important data on a very short timescale.