I don't think it would matter much if you skipped the last meal of solids. Your baby is only 6.5 months old and to be having solids 3 times a day is way more than most. I believe you'll find that on average most mom's only do one feeding of solids per day at this age.
This is not an opinion but what I actually did, I believe you need to do what is right for your baby (what ever that might be). Here is what I did: I had two very large babies and started solids early at 4.5 months with both (max. 1 tbs). I didn't give more than 1 meal of solids until around 7.5-8 months (This is when my boys ate what my Dr. told me what would be considered a serving). Between 9 and 9.5 months is when I started with the third meal. At or around 10 months I did an extra morning snack. Shortly after 11 months I added a second snack. Then a week or two after my boys first birthdays I introduced the final snack to complete the day with 3 meals and 3 snacks. I still bf morning and night until 13 -13.5 months.
I found with my first I was way to concerned with what my child ate. With my second I learned to relax and if I missed a meal of solids my babies always made up for it in milk. So to answer your question, I would go with the flow.
