What's the average age ducks lay eggs?

I've heard of ducks laying as early as 13 weeks and was wondering if it depends on the time they were born/season they mature at when they will lay. I have a pair of Appleyards whom are between 19-22 weeks old and the male's green head feathering is just starting to come in. I also have 2 black/blue female Muscovies that are the same age as them and haven't laid any eggs either.

In total I have a Appleyard pair and 8 Muscovies; 4 male and 4 female Muscovies. None of them have laid eggs and I'm just curious when they will start laying.

I also have another question about coloring. I was told the barring pattern on the Muscovies will fade after time with each molt and wondering if that's true. All of mine are also bibbed and I was wondering if it's possible if some of the offspring won't have it. I would like pure solid colored ducks and would like to breed it out if possible but not sure if it's something reccessive or a dominant trait. I'm still learning colors for them and trying to decide what colors I'm going to stick with.

Thanks for any advice! Here's some pictures too.

Both of my black hens.


Chocolate hen. The male is way lighter.

Big barred boy.

Lavender boy.


Appleyard pair. Drake is behind the female.


Both of the barred and light Choclate. With both of the chocolates and the 2 barred I'm guessing as to sex. With my first bunch (big barred, Lav, 2 black hens) it was obvious but with these guys not so much. One of the barred and the lighter chocolate seem to have a longer body, so I'm assuming 2 boys/2 girls.