I understand that you may be concerned about testing positive to group B strep and not getting the antibiotics in time but dont be.
Group B strep is very common and yes even though there is a chance that your baby may become ill if you dont get the antibiotics in time it is very slim.
I am a midwife and I have cared for many women who have had group B strep and some have been treated with antibiotics and some havent and I have not seen any problems with either.
The little tube they put in the babys belly goes in through the mouth to the stomach where we withdraw a little fluid to send to the lab, we also take a long cotton bud and wipe that in the babys ear (not in the ear canal) and we send that off as well.
We dont routinely test for group b strep anymore, we only treat the women who have had previous positive group b strep, we just monitor the babys temperature, and send the samples to the lab.
I really dont think this should be a reason to choose to have a ceasarean section as it is very rare to get a undesirable outcome.
Ultimately the decision is yours but dont let this decision be made just because you have tested positive to group b strep.