Hi Judy,
I didnt have full placenta praevia but my placenta was sitting ont the edge of my cervix and was posterier at the 19wk scan. I was advised that I needed to go for another scan at around 33wks to see if it had moved up as the uterus stretched.
I went for my scan on Tuesday and they found that it had moved up just enough to have a vag delivery.
She also had to do a scan from down there to double check that the cervix was clear of the placenta and it came out that I was okay.

I am surprised to hear that they were doing scans to check earlier than that on you as my midwife and sonographer said that the placenta can still move up with the uterus up until 34weeks.

Thinking of you and hoping that you get another VBAC.