When did you stop fortifying milk/formula?

Just curious when your low birth weight babies no longer needed extra calories. I have a severe IUGR baby born at 3lb 14oz at 35+5 weeks. We started fortified breastmilk at 5 days old, then after a month switched to neosure 22 cal, now on Alimentum mixed to 22 cal. At first our pediatrician said at least 6 months, then the next appointment she said a full year, shes been gaining over 2lbs a month now so she most recently said “we’ll take it one month at a time”. Im happy to do whatever my LO needs but im curious when other parents no longer needed to fortify or if they fortified every bottle.

Not fortifying would make life easier i wont lie. I was gifted a baby brezza that i may not get to use because it wont be the right ratio. I do throw in a bottle of regularly mixed formula when we’re out of the house without a fridge because the ratio to mix to 22cal would waste a decent amount of formula. Please let me know your experience!!