They don't want you to get anywhere near 32F where the solutions might
freeze.  Just below might be worst, actually, since it might be the
best way to fraction out anything with a lower freezing point.  But as
I understand it, the concern is primarily a theoretical one -- I've asked
a few Kodak chemists about it over the years and they could not think of
any studies that directly bore on the question for modern color chemistry.

The 5L storage bottles are not terribly useful as unless you use 5L at a
time, you'll be opening and closing them constantly, introducing air or,
should you freeze the solutions, worse still introducing air *and* freezing
and thawing them.

FWIW, my father, who was at one time a chemical engineer, strongly suggested
not freezing the concentrates, which jibes with my own limited understanding
of the accidental-distillation process which is the basic concern with
freezing the chemistry and with what one acquaintance at Kodak said to me
a few years ago.  Probably worst is that you'd have to freeze and thaw the
concentrate solutions every time you wanted to mix working stock -- not a
good thing.

I expect good results, as I said, freezing the dilute solutions in smaller
containers after mixing the entire 5L kit.  If that turns out to not be
so, I'll mention it here.