Babies can wake from habit pretty early on, but a lot of babies also need a feed overnight through the first year. That said, I have a couple of thoughts!
My first suggestion would be to stop changing her overnight. At 3 months, unless she's had a huge poo, or she's been having major problems with diaper rash, just slather on diaper cream at the start of the night, and leave it be. Otherwise, it'll start reinforcing the waking and wake her up even more. For nightwakings, you really want to treat it as night - very little light and little interaction.
Next, it's really normal to have 1 or sometimes 2 nightwakings at that age too. So, after a dreamfeed, she might wake at 2:30 and need to eat and then again in the morning. But, I'd be surprised if she's HUNGRY at 2:30, 5, 6:30 AND 7:30 am unless she's not eating well during the day. Babies are often in really light sleep after about 4 am, so I'd suspect that at least some of those early morning wakings are not hunger. Also, you say she nurses briefly at all those feeds and falls asleep. Do you use a paci? You could try other soothing methods if you're suspecting hunger's not the issue.
Finally, about cutting the dreamfeed - some babies don't even notice the change! In her case, she really seems to need at least some milk overnight, so I'd be reluctant to get rid of it yet. Hope that helps a bit!