When to change to a bigger paci?

RTaylor12

My DD loves the MAM pacifiers, and we have two in particular that she always uses. Because we only had the two, we ordered four more about a month ago that turned out to be for 3 mo and up. (Didn't know they weren't the exact same until they arrived.) So we saved them to use later. Here we are at three months and there's still no problem with the old ones. Am I supposed to give her a bigger pacifier starting now? I'm confuzzled.