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The heliospheric magnetic field (HMF) exhibits local inversions, in which the field ‘bends back’ upon itself. Candidate mechanisms to produce these inversions include various configurations of upstream interchange reconnection; either in the heliosphere, or in the corona where the solar wind is formed. As such, explaining the source of these inversions, and how they evolve in time and space, is a crucial step towards explaining the origins of the solar wind; a key science goal of Solar Orbiter. Locally-inverted HMF can be identified by the inward (i.e., sunward) streaming of so-called ‘strahl’ electrons. The strahl is a suprathermal population of electrons, which typically propagates away from the Sun as a field-aligned beam. We examine whether the velocity distributions of inward-propagating strahl exhibit different properties to those of outward strahl, as a result of their alternative path through the heliosphere. To do so, we perform a statistical analysis contrasting the properties of inward and outward-propagating strahl observed by the Helios spacecraft, over heliocentric distances spanning ~0.3—1 AU. We find a range of differences in properties between inward and outward strahl populations, and also in how these populations evolve with heliocentric distance. We evaluate these findings in the context of the formation and evolution of inverted HMF, and the strahl populations themselves. We also suggest how our results may be extended by Solar Orbiter, which will make improved observations of the solar wind strahl, over a greater range of heliocentric distances than the Helios spacecraft.