I assume your username is a bit out of date
The process for appointment of CWOs is in ACP20, Personnel Instruction 503 and it isn't particularly detailed.
[li=3]Recommendations for the appointment of CWOs will be initiated by the Squadron Commanding Officer (Sqn CO). CWO appointments will cease on the 20th birthday.[/li]
Recommendations are to be made on Pers Form 5-03; once complete Sqn COs are to pass it to Wing HQ for action. If the appointment is agreed by the OC Wing, the form is to be forwarded to HQ Air Cadets (P2b1) for final approval.
A Certificate of Appointment signed by the Comdt Air Cadets will be sent to the Wing HQ for presentation to the individual. The date of appointment is the date approved by the Wing Headquarters or the date the cadet reaches the age of 18, whichever is the later.
Pers Form 5-03 is mostly personal details of the cadet and it has a box for "additional comments" from the OC.
What else they decide to do in choosing candidates is very much left up to them.