I just wait till my female is in full flower.
When the tops and the nodes have visibly
Several pistils. I know I don't have to tell you but you need around 4 to 5 weeks for seeds to fully mature.
As for your second question, you can do a single branch or cola if you like. Me personally this last round I did 2 whole plants and a single branch on another.
I guess it all depends how many seeds you want, gonna use, or share.
Lol! Your funny bro! Your like one of the most knowledgeable growers around!
You know what youd going you crazy man!
Good luck and keep them new strains coming!