Ron Natalie wrote in :

Well in the ADIZ you darn well better keep squawking that discrete
code to the ground even if you cancel IFR (ATC will usually warn
you about this...violations are a pain in the butt for them too).

Correct me if I am wrong as I have never been in the ADIZ, but in the ADIZ,
you will hear IFR cancellation received, but you WILL NOT hear "Squawk VFR,
have good day"

Naturally, I could understand the pilot being on "autopilot" and by habit
changing to 1200 once they heard the cancellation received but the legalese
of it would be he was never told to change the transponder if my thoughts
are correct above.

I know I'd appreciate that extra warning from ATC.

Allen