2nd year breeding here.
Sperm plugs are super easy to figure out. When you go to pop you male, they'll have a chunky discharge. Typically past 400 grams on the males is when I've seen it start. Some later than others.
Ovulation really just depends on the female. They'll go when they're ready. Any attempt to manipulate it would probably be far too much work given how easy it is just just wait and see. My 5 year old went last year and not this year. It just happens.
For your 13 month old, I would avoid pairing her personally. Even if she does ovulate for some reason... She would hopefully reabsorb. That's a big girl for her age! Though I've got a male sitting at 900 at the same age. Some just hit that big spurt
Aside from that....
Have a plan! Figure out who you want to pair ahead of time. I personally try to avoid hatching normals. Working with BELs and next year hoping to get some pieds going. We'll see what happens!
Even when everything is set up right.... Sometimes nature will still throw a curve ball. I hatched a super small runty one this year. I had to make a few decisions early on. Was ready to cut the umbilical if I needed too and assist fed VERY early because of the lack of absorbed yolk.
Eggs might fail. Kinks or hard belly can happen
That's just quick off the top of my head...