Are we relying on "word of mouth" here or is there an official source publication that can back this up? Can anyone provide the CL-600-2B19/2C10/2D24 AFM or FCOM reference regarding the alleged "requirement" to treat the upper fuselage with Type IV? Has the Cold WX Ops and/or Limitations sections of the Manufacturer's FAA approved AFM/FCOM been revised recently or was there a temporary AFM change?

Did anyone here query the LGB AEG or ACO?

Get it in writing...