Leaking during pregnancy

For those of you that leaked colostrum before delivery, did you notice any particular sensations or anything that preceded the leaking? I'm 20 weeks today and keep hearing about women who started leaking at like 14 weeks! Apparently it's a sign that may predict successful breastfeeding...hoping it happens to me for this reason! My plan is to breastfeed for a year...but I also know you can't really "plan" for these things!