Oh, no! I didn't mean to imply you were doing anything wrong. I just wanted to know how long her naps were. If she's taking 2 x 2 hr naps, that's wonderful!!! It's actually perfect for a 4 hr schedule. As far as how much she "should" be eating, I would consult her doctor for a guideline based on her weight, etc. The thing about the df is to not do it too late, say past 11 pm. It can sometimes disrupt their sleep and cause wakings. It's okay though, most of this is trial and error. Do you feel her night wakings have worsened since trying the df again? After she woke up at 3, ate, then went back to sleep, how long did she sleep? In that sort of situation, I wouldn't do much more than 1.5 hrs of sleep just to preserve the night sleep. But, no, you don't want to keep her awake if she's tired. You'll find that she'll generally wake around the same time in the morning and there's really not much you can do about it. Sure, you can play with adjustments to her bedtime and day sleep, but it doesn't always work. 6:30-7 is great, and you can adjust your day accordingly. If you want to try and keep you day's start at 7, try to hold her off on a feed until then, and she might fall into that cycle. Just be aware of her sleep cues. Also, she may have had trouble getting to sleep for your mom b/c it was someone different.
One more thing about the night waking. She seems to be waking at the same time, but 3 oz is a pretty good feed for a 3 mo. It may be hunger. Can she take any more during the day? Maybe an additional .5-1 oz with each feed?