I have been doing my research for awhile 2o months bfing slightly below what my baby needs now. and what I have research so far use FM that is closest to bm heard from other mummies illuma first then nan. add 1 scoop during bottle feed. slowly add 2 and 3 then cut off BM.
https://sg.theasianparent.com/transitioning-to-formula-how-to-choose-the-right-formula-milk-after-breastfeeding
Advisable to mix first by adding more formula milk and lesser breast milk