  We investigate the potential of using a sample of very high-redshift
($2\lesssim z \lesssim6$) (VHZ) Type Ia supernovae (SNe~Ia) attainable by the
James Webb Space Telescope (JWST) on constraining cosmological parameters. At
such high redshifts, the age of the universe is young enough that the VHZ SNIa
sample comprises the very first SNe~Ia of the universe, with progenitors among
the very first generation of low mass stars that the universe has made. We show
that the VHZ SNe~Ia can be used to disentangle systematic effects due to the
luminosity distance evolution with redshifts intrinsic to SNIa standardization.
Assuming that the systematic evolution can be described by a linear or
logarithmic formula, we found that the coefficients of this dependence can be
determined accurately and decoupled from cosmological models. Systematic
evolution as large as 0.15 mag and 0.45 mag out to $z=5$ can be robustly
separated from popular cosmological models for the linear and logarithmic
evolution, respectively. The VHZ SNe~Ia will lay the foundation for quantifying
the systematic redshift evolution of SNIa luminosity distance scales. When
combined with SNIa surveys at comparatively lower redshifts, the VHZ SNe~Ia
allow for a precise measurement of the history of the expansion of the universe
from $z\sim 0$ to the epoch approaching reionization.
