first thing take out the cereal.
its most likely causing your LO tummy upset. Contrary to populate belief, cereal does NOT make a child sleep longer. In fact often times it can make it worse as they get gas, tummy upset, or even constipation.
Then I would suggest a slight change in your routine. Your day starts of great and he seems to be getting the sleep needed while at daycare. Where you may be having the problem would be your evenings. Your DS is overtires by bedtime.
Have your DH put him down for a nap at no later then 5. Make it a cat nap. No more then 45 minutes.
Here's the part you may not like.
Move bedtime from 8:30-9 to 7-7:30. do your bedtime routine at about 6:30 and into bed after the last bottle by 7. This way he isn't overtired and he's more likely to sleep longer. Do a dream feed right be for you go to bed. 10:30 is a good time. Then when he wakes if he's hungry feed him. If he wakes and he isn't crying leave him be. I know its hard to sleep with the noise but its better this way. After a few nights he'll know how to get himself back to sleep. He's learning to self sooth. If he's crying do pat/shush or PU/PD try not to rock to sleep as this will cause more problems in the long run.
Also at each feed try to encourage your DS to take more formula. He may have hit his 4 month growth spurt.
HTH