Thanks for the reply.
This leads to a second question. The rules state that when a fleet tries to pass by Gibraltar (or Copenhagen) they have to undergo the fire from the fortress guns and then a fleet (or squadron(s)) in the fort automatically intercept those naval units. Can the intercepted fleet attempt to evade by rolling dice? It sounds to me like they cannot and can only evade by the play of a reaction card but my opponent thinks they can still try to evade in the normal manner.
Your opponent is correct, the intercepted fleet can attempt to evade. Rule 13.8 is just saying that no interception die roll is needed. Interception is automatic. 13.33 says intercepted fleets may evade by making a modified two-dice roll.... There's nothing in either section that says a fleet 'running-the-guns' can't make an evasion attempt.