Unless there is a freezer thermometer sitting inside the refrigerator's
freezer (available at hardware stores and many grocery stores), the Rule
of Thumb I always use is "Is your ice cream hard to scoop out, or
soft-serve?" If the answer is "hard" - keep EBM 3 months, if
"soft-serve" - keep EBM 1 month. The freezer needs to be a deep-freeze
type to store safely for 6 months. This is, IMHO, conservative and
definitely appropriate for sick babies in an NICU - healthy term babies
at home have more leeway, I think.

Also, I tell mom to store the milk along the back wall of any freezer as
the air is coldest there; also store it on a low shelf (as cold air
sinks when the door is opened).

I will obtain the equivalent freezer temperatures for these Rules of
Thumb if anyone wants to know. (Amongst other things, I am a certified
Master Food Preserver volunteer with the Common Ground Project of the US
Department of Agriculture, Univ of Calif Davis Extension Services - I've
got great recipes from them for the BEST "quick pickles" in case your
garden is overproducing at this time of year... private email only!)

Katharine West, BSN, MPH
Sherman Oaks, CA