There are 2 ways to read it - neither is clear.
There are those that argue that you can always snap fire all your guns as the core vehicle rules tell us that we can so long as we move at cruising speed or less
The alternate argument is that flyers rules are more specific and don't allow you to fire more than 4 weapons regardless of distance (unlike other types of vehicles with mention snap shots)
Personally - I agree with the later reading.
There is no firm answer here. You need to talk to your opponent basically or your TO
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