I just know from my past experience from when we went in May. You use your room key to "pay" for your
DDP meals. At the end of the meal, you give it to the CM and they deduct the credits from your total. It gives you a total of the amount of credits you have for the rest of the trip. They lump all the credits (adult and children) together. For example, we had 2 adults and 2 children staying for 7 nights. So we had a total of 28 TS meals, 28 CS meals, and 28 snacks. It did not say (at least not in November) 14 ADULT and 14 CHILDREN TS meals, etc.
However, written ON the room key, it says how many adults and how many childrens are on your meal plan. Our said 2A , 2C.
So, when you go to a TS meal, you can ONLY order 2 adults meals and 2 childrens meals at that seating. The CM knows you have only paid for 2 adults and 2 children, so they will only allow to order 2 adult meals and 2 childrens meals at that seating.
However, if you go to the counter service, it will only let me order 2 adults meals at that time (because of the 2A on my card). Meaning, I could got through the line and order 2 adults meals. Then, I could go through another line (or have my husband go) and order another 2 adult meals. There was no way for them to track how many adult or child meals for CS I got at all.
So, I guess, some people were abusing the system and getting adult counter service meals with their childrens meal credits. They will probably start seperating the adult and childrens credits on the receipt and keep track of adult and children credits seperatly.
BTW, all snack credits are the same for all people (adult or child), so far...