A.C.
I think 13 months is too young to take away the pacifier. My son was 23 months when I cut the tips off, but he was old enough to understand that they were broken. I don't think a 13 month old can really grasp that concept. Also, just because the daycare has a "no pacifier" rule, that doesn't mean that you can't give him one at home. You're right, he is going through a lot of changes, and he has to have something familiar to comfort him.
One more thing - I hate to say anything negative about your daycare since I don't really know anything about it, but it concerns me that they would make a child give up a bottle and a pacifier before they can move to the next class. If you really like the childcare center, then that's great, but if you are bothered by this rule, then you might want to start looking for a center that treats the children as individuals. Not all children are ready to give up bottles and pacifiers just because they turn 1. I have worked at a few daycare centers (and my mom actually owns one), and they don't have such strict rules. Just something to think about.