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We request 5 orbits to observe the interstellar object 2I-2019 Q4 (Borisov) during the post-perihelion portion of its orbit comma once it comes out of the HST solar avoidance region in mid-January 2021. Photometry from HST and from the ground shows that the comet is still bright comma consistent with continued CO-driven activity comma and that it is likely still to be bright enough to observe when it emerges again from solar conjunction. The requested data will be combined with high quality ground-based data comma and HST imaging data obtained from several programs to perform detailed thermal modeling of the comet.s activity comma search for structures in the coma comma and to perform high precision astrometry on the outbound orbit to model the non-gravitational forces acting on the nucleus. This is a unique object comma only the second of its class discovered. 2I is now past perihelion at a heliocentric distance of 2.7 au and is heading out of the solar system and will never return. There is intense scientific interest in this object because it is likely a remnant of the planet building process from an exoplanetary system that we have been given the opportunity to observe in close detail comma thus it is important to finish the observations necessary to fully utilize the huge scientific investment already made on this object.