I also came down with flat foot.
After coming back from Brunei, I developed sharp pain in the
soles of my feet.
My MO explained that long hours of carrying heavy loads during
outfield caused the arches in my feet to literally collapse.
I was referred to a physiotherapist, who decided that my
collapsed arches were not severe enough to warrant a downgrade.
However, I was given 'excused lower limb activities' for a few
weeks.
I've experienced that before, but I did nothing about it.......and
then it turned out I did not have to chiong sua anymore.