I'm 7 months pregnant and im going to be a stay at home mom so il be breast feeding more than half of the time but i would like to have milk saved in the freezer just in case some one else has to feed baby or we are out in public. What pump would be best for occasional use electric or manual? and how many times a week/day should i be pumping for a freezer stash??? also what time of the day?? also do i feed my baby on one breast or both when pumping?