The destruction of Aharonov-Bohm (AB) caging by interaction and the emergence of interaction-induced chiral currents in flux lattices are two paradigmatic examples of interaction-driven quantum transport. While various mechanisms, such as bound-state formation and chiral spectral imbalance, have been proposed, a unifying physical picture remains elusive. Here, we employ the concept of evolution-path symmetry (EPS) and its interaction-induced breaking as a framework to understand interaction-induced delocalization in flux lattices. EPS is defined as the invariance of a path's contribution under combined geometric and phase transformations. We demonstrate that in a $\pi$-flux rhombic lattice, interactions break the EPS present in the noninteracting limit by modifying the phase accumulation of many-body paths, thereby lifting the destructive interference responsible for AB caging. Furthermore, we apply this framework to explain interaction-induced chiral transport in flux ladders, where interactions break the phase relationship between symmetric paths, leading to a nonvanishing chiral current. Our work establishes EPS as a powerful tool for understanding transport phenomena beyond conventional eigenstate analysis.

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• Bose-Einstein condensates
• Cold atoms & matter waves
• Cold gases in optical lattices
• Bose gases
• Mean field theory