Question: What was formed in 2009 by members of For All We Know and Paddock Park,  Air Traffic or Sleeping with Sirens ?

Context paragraphs:
Air traffic management: Air traffic management is an aviation term encompassing all systems that assist aircraft to depart from an aerodrome, transit airspace, and land at a destination aerodrome, including air traffic control (ATC), air traffic safety electronics personnel (ATSEP), aeronautical meteorology, air navigation systems (aids to navigation), Air Space Management (ASM), Air Traffic Services (ATS), and Air Traffic Flow Management (ATFM), or Air Traffic Flow and Capacity Management (ATFCM).

Air traffic obstacle: An Air traffic obstacle is a tall structure which can endanger air traffic.  Air traffic obstacles have to be marked in most cases with red and white colored markings and with aircraft warning lights at night.  On larger structures blinking lights are required.  An example of an air traffic obstacle is the air traffic control tower.

NATS Holdings: NATS Holdings, formerly National Air Traffic Services and commonly referred to as NATS, is the main Air Navigation Service Provider in the United Kingdom.  It inherited the traditions of UK air traffic control, which (founded over Croydon Airport) was the world's first air traffic control regime.  It provides en-route air traffic control services to flights within the UK Flight Information Regions and the Shanwick Oceanic Control Area, and provides air traffic control services to fourteen UK airports.

Control zone: A control zone (CTR or controlled traffic region) in aviation is a volume of controlled airspace, normally around an airport, which extends from the "surface" to a "specified upper limit", established to protect air traffic operating to and from that airport.  Because CTRs are, by definition, controlled airspace, aircraft can only fly in it after receiving a specific clearance from air traffic control.  This means that air traffic control at the airport know exactly which aircraft are in that airspace, and can take steps to ensure aircraft are aware of each other, either using separation or by passing traffic information.

Sleeping with Sirens: Sleeping with Sirens is an American rock band from Orlando, Florida currently residing in Grand Rapids, Michigan.  The band was formed in 2009 by members of For All We Know and Paddock Park.  The group is currently signed to Warner Bros.  Records and have released four full-length albums and an acoustic EP.  They rose to fame by their song "If I'm James Dean, You're Audrey Hepburn" which is the lead single from their debut album "With Ears to See and Eyes to Hear" which released in 2010.  The group's third album "Feel" debuted at No. 3 on the US "Billboard" 200, and a fourth album entitled "Madness" was released on March 17, 2015 through Epitaph Records and spawned the single "Kick Me".  Their fifth studio album, "Gossip", was released on September 22, 2017 on Warner Bros.  Records.  The group is known primarily for the versatility of vocalist Kellin Quinn's leggero tenor vocal range, along with the heavy sound used on their early work and the pop influences they used later into their career.

We Are Defiance: We Are Defiance is an American metalcore band from Ocala, Florida.  Founded in 2009 by former Sleeping with Sirens and Paddock Park singer Brian Calzini, the band released their only album, "Trust in Few", in early 2011 on Tragic Hero.

Brian Calzini: Brian John Williams (born October 25, 1985, in Ocala, Florida) is an American metalcore vocalist.  He formed bands Paddock Park, Sleeping with Sirens and We Are Defiance, his current band.

Air Traffic: Air Traffic are an English alternative rock band from Bournemouth.  Formed in 2003, the band consists of Chris Wall (piano, lead vocals), David Ryan Jordan (Drums), Tom Pritchard (guitar) and Jim Maddock (bass guitar).

ATC Zero: ATC Zero (Air Traffic Control Zero) is an official term used by the U.S. Federal Aviation Administration (FAA) that means the FAA is unable to safely provide the published ATC (air traffic control) services within the airspace managed by a specific facility.  The term is always used in conjunction with a facility reference.  FAA ATC facilities include Air Route Traffic Control Centers (ARTCC); Terminal Radar Control facility (TRACON), Air Traffic Control Tower (ATCT), Flight Service Stations (FSS), or the Air Traffic Control System Command Center(ATCSCC).  The term is defined in FAA Order JO 1900.47, Air Traffic Control Operational Contingency Plans.  It is one of three designations used by the FAA (ATC Alert, ATC Limited, and ATC Zero) to describe degraded operations and invoke operational contingency plans.

Air traffic controller: Air traffic controllers are personnel responsible for the safe, orderly, and expeditious flow of air traffic in the global air traffic control system.  Usually stationed in air traffic control centers and control towers on the ground, they monitor the position, speed, and altitude of aircraft in their assigned airspace visually and by radar, and give directions to the pilots by radio.  The position of air traffic controller is one that requires highly specialized knowledge, skills, and abilities.  Controllers apply separation rules to keep aircraft at a safe distance from each other in their area of responsibility and move all aircraft safely and efficiently through their assigned sector of airspace, as well as on the ground.  Because controllers have an incredibly large responsibility while on duty (often in aviation, "on position") and make countless real-time decisions on a daily basis, the ATC profession is consistently regarded around the world as one of the most mentally challenging careers, and can be notoriously stressful depending on many variables (equipment, configurations, weather, traffic volume, human factors, etc.).  Many controllers, however, would cite high salaries, and a very large, unique, and privileged degree of autonomy as major advantages of their jobs.

Supporting paragraphs: Sleeping with Sirens Air Traffic
Answer: Sleeping with Sirens