Triple feedings?!

My mo/di boys were born on Monday at 36 + 4. I am currently home with one baby and the other is in the NICU. While I'm the hospital the staff had us use a triple feeding system meaning I will breastfeed the baby for 15 minutes, then feed baby formula, then pump my breasts and feed baby some of that breast milk. This process is overwhelming and takes A LOT of time. Has anyone experienced this and have any advice? Or is there any other way of feeding that isn't as busy?! Help 😩