I'm using s6 and my font remains set. Try adding the
KEYMAP=us
to /etc/vconsole.conf. For reference, I'm using Terminus font in tty as well, with the font being in /usr/share/kbd/consolefonts/ter-c12n.psf.gz so my /etc/vconsole.conf is:
FONT=ter-c12n
KEYMAP=us
You can check what's being done by taking a look at /etc/s6/sv/console-setup/shell_up:
#!/bin/sh
[ -r /etc/vconsole.conf ] && . /etc/vconsole.conf
TTYS=${TTYS:-6}
_index=0
while [ ${_index} -le $TTYS ]; do
if [ -n "$FONT" ]; then
setfont ${FONT_MAP:+-m $FONT_MAP} ${FONT_UNIMAP:+-u $FONT_UNIMAP} \
$FONT -C "/dev/tty${_index}"
fi
printf "\033%s" "%G" >/dev/tty${_index}
_index=$((_index + 1))
done
if [ -n "$KEYMAP" ]; then
loadkeys -q -u ${KEYMAP}
fi
You can try those commands manually in the console to check if everything is going ok.