My babies cluster fed for an hour or more almost every evening the first 2-3 months. This is also normal but for me was stressful because at first I thought my first baby was doing this because she was starving. My breasts felt empty and I was convinced I wasn't making enough and she was still hungry. In reality, they often cluster feed in the evening because you have mostly thicker fatty milk left at that time and it's work to get it out. So they work a bit and it tires them out and they fall asleep. But soon after they wake up again crying to be fed. Rinse and repeat. But eventually they have tired themself out getting that thick fatty milk, and have a big full belly and they're all set up for a good chunk of sleep! So just hunker down in the evening with a drink and a snack because it's normal if a little tiring. The longest my daughter did this was 6pm-2am (only once thank god) but 6-8pm was standard.