I've found solids not to affect the amount/volume of bf's at that age. Regardless of how much and when they have it, they both would still have their scheduled bf. They know for themselves what they require from their diet, and its still from the milk, so they will pick the times and volume they want. They go buy more of a 24 hour clock, and how much they have had in that time period. I was always warned though not to try to force to much solids on them, and let them allow to give you signals when they want more solids, otherwise it may interfere with their milk intake, which is more important. I think it would be that if they have to much solids in their belly, they can't fit the amount of milk in they want and can feed more often or get tummy pains.