Star Wars Armada: does a squadron command give a squadron an extra turn?
TLDR: Squadrons only activate once per turn

Per the Armada Rules Reference on page 12, squadrons Activate when one of these happens:


In the Squadron Phase (with the limit of either Moving or Attacking, but not both)
In the Ship Phase when a ship resolves a [squadron] command (with the ability to both move and attack)


But at the end of any activation you toggle the Activation Slider for the squadron to indicate that it has been activated. 

Further, you cannot activate a squadron if the color of its Activation Slider does not match the Initiative Token. This includes squadrons with the Rogue keyword as that keyword applies when they Activate.

The net result of this is that you can either activate during the Ship Phase or during the Squadron Phase, but not both.