Formula and Breast milk rotation

Co

For various reasons I have weaned from

nursing and pumping and we have introduced formula as well as using up my BM stash. Our pediatrician stated to give the formula as a separate bottle then the BM vs mixing since we are going to all formula. For you mommas who do this do you have a schedule you give one bottle over the other. Like do you give a bottle with BM morning, noon and night and bottle of formula in between?? Right now we are doing 1.5. oz of BM bottle and then separate 1.5oz of formula every feeding and there are not enough bottles in the world to keep up on this. Thoughts?