Navy air blockade?
Haart, in a word: No.
No Fly zones are always more complex than they sound. For example, what would a T45 do if the enemy decided to stay on the ground and roll up the rebels with tanks. Also, how do you deter or coerce when your only option is to vapourise or ignore.
Bottom line is a shooter at range is a very blunt instrument and easily negated or foiled. Form a legal basis it would also be difficult to prove a self defence linkage. Better to let the T45 do what it was designed to do and protect the fleet.