Jesus, I phucking hate to repeat myself. =) Please look more closely. I was referring to the risk on the LONG CALL after assignment on his short call. The position dissects to a synthetic otm back-month long put IF the short call is assigned:
Assigned call = short stock
Short stock + long deferred call = synthetic long deferred put.
The put has minimal short duration vega risk, but it's short about 30 deltas and short theta.
Assigned call = short stock
Short stock + long deferred call = synthetic long deferred put.
The put has minimal short duration vega risk, but it's short about 30 deltas and short theta.