Try monster cropping. cloning out the plant before flipping to flower or just after. then growing the clones out repeating.
need a 2nd space/tent for this and light.
That totally depends on how long you wanna veg a plant, how big you want your plants to be before switching to flower and how powerful of a veg light you got. You can always prune back if you veg for too long.
Depends on how much space you want to dedicate to doing it. A small propergation tent can help shelve times off between grows. You could start your next batch probably the week before harvesting current batch.