A multiplylensed galaxy, MACS0647JD, with a probable photometric redshift
of $zsimeq 10.7^{+0.6}_{0.4}$ is claimed to constitute one of the very
earliest known galaxies, formed well before reionization was completed.
However, spectral evidence that MACS0647JD lies at high redshift has proven
infeasible and so here we seek an independent lensing based "geometric
redshift" derived from the angles between the three lensed images of
MACS0647JD, using our freeform mass model (WSLAP+) for the lensing cluster
MACSJ0647.7+7015 (at $z=0.591$). Our lens model uses the 9 sets of multiple
images, including those of MACS0647JD, identified by the CLASH survey towards
this cluster. We convincingly exclude the low redshift regime of $z<3$, for
which convoluted critical curves are generated by our method, as the solution
bends to accommodate the wide angles of MACS0647JD for this low redshift.
Instead, a best fit to all sets of lensed galaxy positions and redshifts
provides a geometric redshift of $zsimeq 10.8^{+0.3}_{0.4}$ for MACS0647JD,
strongly supporting the higher photometric redshift solution. Importantly, we
find a tight linear relation between the relative brightnesses of all 9 sets of
multiply lensed images and their relative magnifications as predicted by our
model. This agreement provides a benchmark for the quality of the lens model,
and establishes the robustness of our freeform lensing method for measuring
modelindependent geometric source distances and for deriving objective central
cluster mass distributions. After correcting for its magnification the
luminosity of MACS0647JD remains relatively high at $M_{UV}=19.4$, which is
within a factor of a few in flux of some surprisingly luminous $zsimeq
10$$11$ candidates discovered recently in Hubble black field surveys.
