Baby waking up early

So, my baby is about to be four months and she has always fallen asleep on her own. After a feeding and pajama change, read a book and lay her down awake. She usually falls asleep within about 15-20min.

She has been waking once in the early am around 5am consistently, however we took a trip to Texas where she woke up at 3am and 5am to eat. Now that we are back she is still getting up at 3am on the dot.

Me and my fiancé can not sleep and are going back to work soon- how can I get rid of the 3am waking?