My 9month old son who is breast fed has for the...

My 9month old son who is breast fed has for the last few days not wanting to be fed through the day, he loves his solids but wont breastfeed and he also wont drink formula. I was wondering if anyone has had this happen to them or if you have any advice that would be great. He is however drinking through the night, but was wanting to stop this as i am returning to work soon and will be doing night shift. Any advice would be great. Thanks