Hello and welcome to Baby Whisperer forums.
Baby wise and Baby Whisperer are two different sleep training methods.
If you'd like to follow Baby Whisperer methods there will be differences.
I would just feed your LO when she wakes at 12.30am, it's totally normal for a baby this young to need to feed more than once in the nights. If you go ahead an feed you'd likely get another longer stretch before the next E time rather than getting up again an hour later to re-plug and resettle and then another hour later to feed. I'd just feed and get everyone back to bed. Sounds like she's hungry.
hth