I had a similar situation was all ready to have a vbac until diagnosed with gd at 32 weeks. My ob planned for me to have a c sect as I was put on insulin then taken off it due to a reaction. I was resigned to having to give up my vbac dream.

In the end though I went into pre term labour at 35 weeks, I was put onto medication in the hope that I made it too 38 weeks. At 37 weeks my waters started to leak. My ob let me progress through the labour but he had me prepped for a c sect jic. In the end I gave birth by vbac 45 minutes after my waters were fully broken. Dd was on the smaller side at 2.75 kilos and had to be admittted to the scn because I had been on insulin even though I wasn't when she was born, her sugar levels were all fine.

So don't give up hope, fingers crossed you go into labour on your own.