ring up to complain and find out why??
We leave a supply of nappies at nursery and if they run out that day, my boys have often come home in a different nappy - I always assumed they have run out (although they usually write it in the book) and send some more in - it wouldn't even occur to me to ring up to complain about it. I would rather they were changed into a different nappy than left in a wet/dirty one because there were none left!!
Was chatting to another mum at a party at the weekend and she was telling me this story about how her DD came home in a different nappy (along the tone of '...and it was a Huggies one and I use Pampers so I rung up....') - I was at it as surely there are more important things to worry about??
Yes, it means another baby is a nappy short but I assume they will use one of mine for another baby in the same situation so it probably evens itself out.