Regarding the weight issues, yes it is difficult to maintain it, specially if your body is growing and can't adapt to your supposedly weight categories. That's why there are different type of weight classes, so that boxer can fit where they height and body will go. Then go up another notch like what Manny did during his prime and beating large fighters. So for Jerwn, and it the news is true that he can't make the weight properly then it will be a very dangerous fight for him and most likely he might lost again. But if his team are good at working with him round the clock to check how his body is losing that weight, and not body mass, and then still retain his power at absolute peak prior to the fight then they do a good job and most likely Ancajas will have his revenge.