i have a pretty consistent pick up time (or at least a window) of when i get my DS from daycare...usually my DS finishes his last bottle right before i get there or is due for a feeding within my pick-up window so the daycare is warming his bottle of breastmilk...

i don't want to stick around for him to have his last bottle so i'll take the warmed bottle with me...once milk is warmed up, do i need to give it to him immediately? or can i save the bottle for another instance (which means i would have to re-warm it)?