HM... so maybe you could move that 6pm feed closer to 5:30 and add another one at 8pm right before bed? then you wouldn't drop this one bottle you're talking about and she would still be getting 8pm feed to keep her asleep at night.
she may not want full feeds both times so maybe you could do 3/4 a feed at 5:30 and 3/4 at 8.
I won't say introducing cereal at such a young age is sth terrible as we tried some at maybe 4,5 months with our dd but actually if you're planning to introduce it in hope she'll be getting more food that way- well, it doesn't really work like this. milk is still essential at her age so do keep on feeding her those bottles!
HTH
Monika