I start advertising as soon as I know I will have an opening. I started getting contacts for Sept in January so if you are looking to fill for sept worth advertising now. Especially put ads up on things like daycarebear, godaycare, etc that are kept as a data base. When you list on something like kijiji you have to keep on top of your ad or it will disappear into the multiple of pages so you need to remove and repost frequently.