On a recent IFR training flight, I left the code of the first segment on for the second leg out of Class G, and ATC didn't flinch..
I saw somebody do this out of YBLT last week, as I was recieving the departure I see somebody squawking 4226 (from memory) heading in the same direction. If it wasn't you then it was somebody else doing the same thing.
That code would probably have been reassigned to another flight, and if they were taxying or flying, and their flight plan not yet coupled up to a radar return due to being out of range of radar, and if you were within 8nm of their flight planned track, their label would attach to your aircraft. Not good.
My options when seeing such:
have a good bleat to the pilot about code 2000.
minimise the chance of incorrect coupling by getting the aircraft on the right code soonest.
I was having a bad day, and had just grumped at a VFR who was telling me a bunch of stuff I did not need to hear, so considered I had hit my grumping quota for the hour. If I get an incorrect coupling in these circumstances I'm required to submit an incident report, what CASA does about it I have no idea.
When in doubt, do what the AIP says
your code for your sector B to C is ....."
not sure if it's a legitimate procedure though
Sure is. Isn't documented anywhere, but isn't documented not to do it either
. I'll do it if the pilot requests it, but would not initiate it. Pissable potfall, erm, possible pitfall is if the pilot submits a DLA message the code will detach from the flight plan, and next time it hits that 45 minute parameter it would probably not get reassigned the same code.