When tightly-knit communities suddenly show electoral volatility, does it signal weakening group identity, or does it reveal something deeper? This question matters wherever centralized authority structures shape bloc voting. Conventional wisdom interprets such shifts as boundary erosion. This paper presents evidence for the opposite.Drawing on an extreme-case design, I exploit a natural experiment — Israel’s 2019–2022 political deadlock — to track voter transitions within ultra-Orthodox communities, where ethnically distinct subgroups maintain near-total political separation despite shared religious practice. Using ecological inference on ballot-box data from five population centers across six elections (2019–2022), I find exceptionally high baseline party loyalty (90–95%), a dramatic disruption during the March 2020 – March 2021 transition when switching surged to 12–19%, and a swift return to high loyalty within 13 months — though the shifted voters remained with their new parties.The synchronized switch of voting loyalty across geographically dispersed cities, occurring without residential mobility, is consistent with elite-mediated bloc realignment rather than emerging voter independence. Paradoxically, the capacity for mass switching may reflect stronger, not weaker, institutional control.These findings challenge how scholars of party–voter linkages interpret electoral volatility in identity-based voting blocs: apparent instability may reflect disciplined coordination, and what looks like boundary erosion may actually reveal institutional strength operating through collective action.