We accidentally stopped at 8 months (we went away I forgot the Milton's they didn't have any where we were so had to roll with it as we couldn't sterilse in the bathroom sink of the hotel due to a leaky plug) and ended up rolling with it
I stopped at 10 months with my youngest. Purely on the basis that my oldest touches baby etc. and by this point my youngest was not only weaned but eating anything in sight ie toys and things. I do still make her formula with a bit of hot water mixed with cold filtered water so the water isn’t hot but is sterile?
The formula still goes off like normal formula. We used neocate (no boiling water for that too) and we still sterilised until she moved onto milk alternative at 15/16 months. X