Hey Kris, I don't know about 'length', but I believe that if this is your 2nd bub, your cervix may have had a head start in the dilation department, so doesn't necessarily mean baby will come early. Having said that, there's no harm in doing everything you can to encourage the situation LOL. Going for walks, climbing stairs, straddling chairs (keeping pelvis open), bouncing on fitball etc, to keep bubs head moving down and therefore signalling to your cervix that it should continue to open on up.
Ooooooh, not long now! I'm so excited for you!