I am gg overseas for 11 days soon (without baby). Baby has always been on breastmilk so far. But due to a recent bout of illness, I'm not able to stock up enough frozen bm to last my whole trip. Based on my calculation, she will need 6 x 150ml per 24 hours - so I should need about 66 packs. but I'm possibly only able to store about 50 packs. So, very reluctantly, I think I'll need to introduce fm for 1 feed per day. which brand should I try? And how do I intro fm? If I only want to substitute 1 feed/day, how much should I feed her?