I agree with Crystal...Over the years, I have had several older kids make innocent comments regarding changes in their d/c and they are simply talking about their lives and I have always asked the parent's the next time I see them, if something will be changing.
However, under NO CIRCUMSTANCES do I believe it is at all appropriate to tell a child they are being replaced! This is extremely unprofessional!
In the case of the OP, it could be the new d/c doesn't have any openings until after the holidays. I understand them not wanting to tip their hand and give notice until they need to...they don't want their spot replaced before they are able to make this change. Often times, the parents do not even think about their child saying anything. However, this is HUGE in a child's world and they will!
I agree on allowing the child to see a new d/c prior to enrollment. I think it's the only right to take their feelings into consideration too.