@Uwe's answer to Why would sub-cooled LOX tanks need to “topped-off” until the last minute or so? explains how subcooled LOX is kept cold and dense by "in situ refrigeration"; helium is bubbled through and the evaporation of oxygen into the bubbles removes heat as the helium escapes.
The LOX tank therefore needs to be regularly "topped off" with makeup LOX as it evaporates.
(A cryogenic engineer would like to build rockets like giant dewars, vacuum flasks or thermoses but it adds too much additional weight and complexity and diameter.)
But the RP-1 is sub-cooled as well and is also subject to warming.
Question: Is there any refrigeration for the subcooled RP-1? If not, why would one of F9's cryogenic subcooled propellants require refrigeration but the other not?