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We investigate the X-ray variability of the supergiant X-ray binary 4U 1907+09 using the new NuSTAR observation of 2024. Unlike the previous NuSTAR observations, the source shows significant flux variation during the current one. The light curve exhibits dips (off-state) and flares (on-state). The phase-coherent timing analysis during the on-state yields a pulse period of <mml:math><mml:mn>443.99</mml:mn><mml:mo>(</mml:mo><mml:mn>4</mml:mn><mml:mo>)</mml:mo><mml:mspace></mml:mspace><mml:mi>s</mml:mi></mml:math>, showing the pulsar's continued spin-down. The pulse profiles show an asymmetric double-peaked structure with a phase separation of 0.47 between the two peaks. A cyclotron resonance scattering feature (CRSF) is also detected at <mml:math><mml:mo>∼</mml:mo><mml:mn>17.6</mml:mn><mml:mspace></mml:mspace><mml:mrow><mml:mi>keV</mml:mi></mml:mrow></mml:math>, along with its harmonic at <mml:math><mml:mo>∼</mml:mo><mml:mn>38</mml:mn><mml:mspace></mml:mspace><mml:mrow><mml:mi>keV</mml:mi></mml:mrow></mml:math>, persisting across all flux states. Flux-resolved spectroscopy reveals that the CRSF energy remains constant despite a 25-fold change in flux. The spectral parameters, like photon index and e-fold energy, are out of phase with the pulse shape, whereas the cutoff energy is in phase with the pulse shape. The source's luminosity during the on-state is <mml:math><mml:mn>2.85</mml:mn><mml:mo>×</mml:mo><mml:msup><mml:mrow><mml:mn>10</mml:mn></mml:mrow><mml:mrow><mml:mn>35</mml:mn></mml:mrow></mml:msup><mml:mspace></mml:mspace><mml:mrow><mml:mi>erg</mml:mi><mml:mspace></mml:mspace><mml:msup><mml:mrow><mml:mi>s</mml:mi></mml:mrow><mml:mrow><mml:mo>−</mml:mo><mml:mn>1</mml:mn></mml:mrow></mml:msup></mml:mrow></mml:math>, consistent with a "pencil" beam radiation pattern expected at this flux level from a collisionless gas-mediated shock. These results offer further insights into the accretion dynamics and magnetic field geometry of this system.