Update on the Measurement of alpha_S with a 500 GeV Linear Collider

An update on the prospects for the precise measurement of the strong coupling constant alpha_S at a high energy Linear Collider via the three-jet rate is presented. In particular, the issue of the distribution of center-of-mass energies of the identified q-qbar event sample, which can affect the determination of \alpha_S at the scale Q^2=(500 GeV)^2$, is addressed.Comment: 4 pages, 3 figures, LaTex, requires epsfig and aipproc macro