Any of you mamas possibly on your 2nd or more pregnancies experienced labor as group b strep positive or other ftmommas test positive?

The only thing my doc has said is we'll need antibiotics during labor but at my birth class they mentioned really you should be on them for several hours before giving birth. I'm just nervous about not having enough time for that or getting sent home. I've read stories about mamas that get sent home and go back to give birth within the hour!

Just looking for some reassuring experiences or tips! This is our first baby, currently 36 weeks and just starting to get a little anxious!