They refused to believe that I knew when I concieved, they scans said I was 40 weeks... but she came out looking like a very overdue baby, and every midwife who didn't know my dates said that she was a minimum of 3 weeks late.
Dabhip it can be at least 2 weeks from show/plug to birth. It is not an exact sciene cy all means and you can loose a lot of plus as well.
I just did a birth on Thursday and she lost her plug on Monday, some was still coming out in labour.
I know -personally - 2 women who went past 43 weeks (one went to 43w + 6), their choice. Both had good and easy labour. There would be far more women who would go to 43 weeks if they wanted to. It has to be an informed choice though.
If you go to www.birthlove.com they have a "ten months mama" page with several stories.
I doubt very much you will got to 42 weeks !