We explore the dynamics of long-range pairing Kitaev chain by varying pairing interaction exponent, α. In a finite size system, it is known that Loschmidt echo has periodic revivals for quenching to the critical point. We find that the revivals in the Loschmidt echo are connected to the energy gap at finite size system. Moreover, and contrary to expectations, for the long-range pairing case, α < 1, the first revival time (periodicity) scales inversely with the group velocity at the gap closing point, instead of the maximum group velocity. Analyzing the effect of quenched averaging disorder shows the robustness of the first revival time against disorder. For the dynamical phase transition, the presence of disorder washes out the non-analyticities in the rate function of return probability.