I know that you cannot use a TL acquired by FCS to modify dice in the same attack the TL was acquired. However, because Gunner / Luke counts as a new attack, you may use a TL acquired after the failed attack that triggered Gunner / Luke (this is all very clear in the FAQ).
What is less clear is if that TL is used during the Gunner / Luke attack, does FCS allow you to reacquire?
Really, this is a question about the precise order of events. Here is what I think: 1.) attack dice are rolled, 2.) attack dice are modified if able, then 3.) FCS triggers allowing a TL to be acquired on the defender. This is why it cannot be used to modify the initial attack, it is acquired after the attacker’s opportunity to modify dice – and this would mean FCS would allow you to reacquire anytime a TL is used.
Am I wrong?