Dear Mummies, I'm kinda confused over the lifespan of the breastmilk. If the chilled breastmilk is warmed up till and kept at 40 degree c., how long can it last? still 4 hrs?

Room temp milk can keep 4hrs , normally if I were to give freshly pump milk if bb can't finish I will leave it in my room for later feed. But if frozen milk thawed and heated up I will throw after 1 hour.