Solid food to replace the milk

Starting from how many months can I let my baby to eat porridge to replace milk for a meal? My baby is now turning to 8 months next week. Her feeding schedule as following: 8am - milk 240 10am - egg, fruits 12pm - milk 200 2pm - porridge 100-150 4pm - milk 200 6pm - porridge 100-150 8pm - milk 240 and sleep until next day morning Is that too much eating times? Is it time to reduce one meal of the milk and replace by the porridge?