  Passive galaxies are ubiquitous in the local universe, and various physical
channels have been proposed that lead to this passivity. To date, robust
passive galaxy candidates have been detected up to $z \leqslant 5$, but it is
still unknown if they exist at higher redshifts, what their relative abundances
are, and what causes them to stop forming stars. We present predictions from
the First Light And Reionisation Epoch Simulations (FLARES), a series of zoom
simulations of a range of overdensities using the EAGLE code. Passive galaxies
occur naturally in the EAGLE model at high redshift, and are in good agreement
with number density estimates from HST and early JWST results at $3 \leqslant z
\leqslant 5$. Due to the unique FLARES approach, we extend these predictions to
higher redshifts, finding passive galaxy populations up to $z \sim 8$. Feedback
from supermassive black holes is the main driver of passivity, leading to
reduced gas fractions and star forming gas reservoirs. We find that passive
galaxies at $z \geqslant 5$ are not identified in the typical UVJ selection
space due to their still relatively young stellar populations, and present new
rest--frame selection regions. We also present NIRCam and MIRI fluxes, and find
that significant numbers of passive galaxies at $z \geqslant 5$ should be
detectable in upcoming wide surveys with JWST. Finally, we present JWST colour
distributions, with new selection regions in the observer--frame for
identifying these early passive populations.
