If you are breast feeding, it actually depends on how long you want to continue feeding as to when you swap this around. If you want to wean by 12 mths, then offer food before milk at around 10 mths ish. If you want to continue longer, food is for fun and breast milk can be the basis of diet unti 12 mths. I think this is just to ensure supply is sustained. If you are formula feeding it does not matter that much, as long as they are still getting enough formula to suppliment the solids nutritionally. Most kids are eating enough solids by 10 mths, but if you have a fussy eater, i would still offer the bottle before food to 12 mths to make sure your LO is getting enough of the good stuff.