Storing nic in freezer is best for it's shelf life for sure but if you plan on using it over the next couple of months, I dont think its necessary. Im sure some nicotine vendors have had bottles of nic on the shelf a while waiting on people to buy it. I plan to only make small batches of the base.120-240ml at a time. I wouldnt be worried about that amount not being in the freezer as it will get used fairly quick