I'm in the same boat, Abbysmomma... my LO just turned 5 months and she's getting up anywhere from 2 - 4 times after we put her down at 8:00. Usually she wakes up around 8:45PM and just needs to be soothed, then again around 10;30 if we're not quick enough with the DF! Then, she sometimes wakes again between midnight and 1AM, sometimes not, then ALWAYS wakes around 4 to be fed. Thankfully, usually after that feed she goes 'til 8AM.
When she was 4 months old, we'd put her down at 8:00, she'd get up at 4AM and then again at 8AM. Where did that baby go???
We tried giving her solids at her dinner feed, and, boy, you're right, DON'T do that... she just woke up SCREAMING with gas later on.
She's still on the 3 hour EASY because she's a little peanut (only 12.5 lbs.) and I found that when I tried to stretch it out during the day, she woke more frequently at night. Maybe I should give it a shot again, I don't know..?
Also, she only takes 45 minute naps during the day, so I think the 8:45PM wake is just a carryover of that.
Oy... let me know if you come up with any solutions that work & I'll do the same!