Don't think it matters really, but you should be eating consistantly during the day, read that as getting calories consistantly during the day if you want to grow.
I usually have my protein after my dinner, just because it's more convenient, however I've also used one in the morning if I had a short breakfast, and also have brought it to work if Iknow I might miss lunch or not get a full lunch. Bottom-line is to eat 5 meals a day to grow, and don't miss breaksfast!