The seeded branch needs to stay untill the end of flowering.

As said what you will get from your seeds are. Plants that have either mother traits or father traits or a mix of the 2 or something you have not seen.

If you are looking for the mix, then selective breeding comes up next. You must take only the ones selected and cross those several times to get a stable strain. To stablize a strain is not that easy. You must know what characters your looking for at an early age.

If you just keep seeding the F1 back into itself randomly you will have your own strain but who know what traits it will have. Hopefully the mix you want.