  The rate of charge-parity switching in a full-shell
superconductor-semiconductor nanowire qubit is measured by directly monitoring
the dispersive shift of a readout resonator. At zero magnetic field, the
measured switching time scale $T_P$ is on the order of 100 ms. Two-tone
spectroscopy data post-selected on charge-parity is demonstrated. With
increasing temperature or magnetic field, TP is at first constant, then
exponentially suppressed, consistent with a model that includes both
non-equilibrium and thermally activated quasiparticles. As TP is suppressed,
qubit lifetime T1 also decreases. The long $T_P\sim 0.1$ s at zero field is
promising for future development of qubits based on hybrid nanowires.
