@momofacutie, yes you can mix it :) kellymom.com has the answer to every question. they say am milk has wake up qualities and pm milk has bedtime qualities. like coffee vs sleepy time tea
I was told in the hospital that Daytime pumping and nighttime pumping should be fed around the time the pumping occurs - so if you pumped at night, feed that milk at nigh and etc., And also, other pumping sessions, shouldn't be mixed together. But my baby was in the NICU so maybe that's why?