How long should it take to pump at work?

My baby is 5 months old. She’s been at daycare for a month. She tends to drink much larger bottles at daycare than she nurses at home. At daycare she will easily suck down three 5.5 ounce bottles every day with no spit up, whereas when I breastfeed at home, she doesn’t stay on the breast long and gets easily distracted or will stop feeding as soon as she isn’t hungry anymore rather than breastfeeding until she is full.

At first this was an issue because at daycare she was drinking way more than I was able to pump at work but I’ve been able to successfully get my milk supply up so that I can easily keep up with how much she drinks at daycare. However in order to keep up that supply, I have to pump 35-40 minutes every time I pump and I’ve read I shouldn’t pump more than 20-30 minutes at a time.

It seems to be working fine for us but I’m just curious about how long other moms have to pump to keep up with baby’s demand. Thanks!