For complaints or enquiries, use Form FCS 1521

http://publicapps.caa.co.uk/modalapplication.aspx?appid=11&mode=detail&id=7623

To check progress of application by Biggin Hill, click on

https://www.caa.co.uk/Commercial-industry/Airspace/Airspace-change/Decisions/Biggin-Hill-Runway-03-instrument-approaches/