Freezer stash no good!?

I go back to work in a few weeks. My LO will be 12 weeks old. I started a freezer stash but I found out that my baby does not like the thawed milk! I had been pumping for the last 3 months and now I think it’s all for nothing. I plan on pumping when I go back to work and nurse when I am home. I’m afraid I won’t be able to keep up and not have enough for her. Does anyone just pump daily and not have a freezer stash at all? Any tips ?