I'm nearly 26 weeks, and just had to give my boobs a good ole squeeze to find out if they are producing yet, and my left one lactated just a teeny tiny bit before turning into clear colostrum (was still slightly lactating right until I fell pregnant, 9 months after I stopped expressing), but got nothing out my right one. I get an engorged feeling maybe once a week, but other than finding that glamorous dried crustiness, hadn't seen it properly until now. Completely different to my last pregnancy, where I was able to squeeze it from about 18 weeks.