Thank you all for your thoughts. I'll try to add what I can, but Katie is wearing her crankypants today. I'm so tired and DH is out of town, so it's been a tough day!
We started with Avent bottles and Katie's toots would echo through the house! We switched to the Playtex disposable system with the collapsible liners and it improved dramatically.
She usually passes some gas throughout the day, but not ALL the time and she doesn't have to struggle, bunch up her legs, etc. I noticed this a couple of times when I've slept in her room that after her first wakeup that occurs at 4hr past the DF, she gets gassy. She cries out as she passes it, is bunching up her legs, and not to be gross, but it's much louder than her other toots - like there's more coming out at once or something. She's also very tooty during her breakfast bottle, stopping to pass the gas. Again, she's bunching her legs, crying out and it's quite loud and (if this make sense) forceful.

Sorry, it's really probably TMI!!! But, once she gets it out, either during or shortly after the breakfast bottle, she's fine for the day. I don't know if Gripe Water would help with this or not. But, if I have to get up and give it to her at 2am it's not the prefered solution (but would be better than the current situation). Oh, we put Mylicon in every bottle to prevent gas as well.
I'm sure that her night wakings could be from a number of different things, but I can't help but wonder if this early morning gas is a problem for her (especially since she cries when passing it). So, then what's causing it? Either not burping at the DF which Tracy says they don't need. Or, it's the empty tummy "syndrome" where her tummy gets some air in it once the DF bottle passes through. Then it stays that way until her breakfast bottle "pushes" the air through her system.
We've tried to do the DF before she wakes for it and we're successful for 3 nights, but last night she woke up before we gave it to her.

Other than this feeding at 10/11pm, she doesn't get another feed until morning at 7am - so going 9 hours although waking up at 10/11, 2/3 and then sporatically thereafter. If we drop the DF, would you recommend an early morning feed or nothing from bedtime at 7p til breakfast at 7am? She does eat well at the DF - usually 6oz. Although now, aside from her breakfast which can be 4-5 oz, she's been eating close to 6 oz. in all her bottles. She eats 5-6 oz at daycare at each feed, but sometimes they'll feed before 4hrs and she'll take another full feed (she's had some crying during the adjustment and probably burning some extra calories). So her daily total intake is between 25-30 oz. Her weight is 16 lbs. and I know the guideline is 2 oz per pound, but she's never eaten that much. Also, if I said she eats better during the night, I meant that it's more efficient, less distracted. She can take 45 minutes during the day and anything will distract her - even the change in lighting because the sun goes behind a cloud.

She's 4.5MO and we haven't started solids. Tried 2 bites of applesauce last week (Tracy said fruits are easier to digest than grains) but it tied her tummy in knots. So, we'll give it another go in a couple more weeks. But, with her eating almost 6oz per bottle, we still have some room to add formula.
Oh, and don't get me started on napping at daycare. I'm not happy with the facility we have, but can't change until June (although I'm still looking). She's there for about 7 hours a day and one day slept for a total of 1 hr: one nap of 25 minutes, one of 40 minutes. When DH picked her up, she fell asleep on the way home and stayed asleep once arriving home for a total nap of 2.5 hours. They won't do as I ask for her naps (give in to quickly) and will let her sleep in the bouncy seat. Still will only sleep for very short periods of time. Katie is spirited when it comes to sleep and I get that it's controlled chaos most of the time and they can't spend 20 minutes helping her sleep, but there must be some middle ground and when I asked them, "how can we get her more daytime sleep?" The only thing they said was, "we'll keep trying." I don't think they have a clue about infant sleep at all.
So, I know the naps are contributing, but we've had this restlessness problem for a long time - like December or something. For a while I thought it was Katie's paci addiction, but she can stay asleep earlier in the night without it.
Sorry for this being so long, but you gals had great suggestions, and I wanted to "chat" more about them all. Thanks again. I'm going bonkers with this. Especially starting back to work. I don't know how it's all going to fit. I'm physically tired all the time which pushes me to my emotional limits. Add the rollercoaster of daycare - especially since I"m not happy with the facilty right now. Now I have the intellectual demands of a job and all the stress that goes along with reviewing/analyzing/negotiating contracts and pricing. I'm only part-time right now, but April I'll be full-time. It is definitely taking it's toll...