#1 after they form the 5th node they are considered mature.
After that it is considered acceptable to remove her top.
#2 again after the 5th node.
You will see the branches start to alternate, also a sign of maturity.
#3
Don't prune anything.
the main stems produce leaves, where that leaf joins the stem a branch will form. Just let everything grow. No benefit from removing them.
#4 any leaf that has any green on it will preform photosynthesis.
Ever little bit gives her more energy for growth.
I don't remove leaves at all.
If they fall off fine otherwise I let them be.
Especially in veg and so young.
As long as she is healthy and growing well any time after number 5 you can top her.
I used to follow the Maple Leafs, too painful now.
Congrats on the win, hope they go all the way.
Stay safe
Bill