Can you just not consent to the strep b test? I plan to refuse it as I don't want antibiotics and I'm also planning to homebirth so I'm not sure if it would mean I couldn't.
With my first I tested posititve to the swab and they forgot to give me the antiboitics in labour as it was quite fast. With my 2nd I had a planned homebirth with an independent midwife so it was easy to say I didn't want the swab and she was happy with my choice. I don't trust the swab as the strep b status can change and also it can give false positives, I have heard of someone not actually swabing anything thing and it came up positive!
I hope everything goes well and you can have a homebirth :)