Easy one so I will take it!:)
No pro-rata basis. The day the put deal was done 100 bucks was debited from the buyer's account and into your account.
No going back on this. Whatever eventually happens, exercise or expiry of the put worthless is irrelevant.
Atticus,
You mentioned that the downside risk can be managed in worst case scenario by preferably being cash secured.
How do you manage upside risk? With the underlying at some pre-determined delta?
Thanks,
Rajesh