I found the only way of getting my evening supply up was pumping specifically at those times, after the 1,4,7 feeds and topping her up with that- for like, 3 or even 5 days in a row and then we were back to only off the boob.
It was mainly though related to my own exhaustion.
I needed DH to re settle as both of mine had a habit,pre 3 mths, of doing huge explosive BF poops after EVERY SINGLE FEED....so resettling meant nappy, cream, re swaddle and settle. That's why I wasn't doing it ;-)
S x