When does the Game Round end?

So buckle up lads because it will seem a bogus question but actually it got some interesting consequences in many ITS games.

When does the Game round end?​

Does it end when the second turn player turn ends? (i.e. the active player runs out of orders and/or when he decides not to spend anymore).

In case of a game or scenario condition that forces the end of the match also the game round ends? Or the game skips this phase and goes straight away to match ending not triggering any effect related to the end of game round?

exhibit one:

Mission Frostbyte Killer Cold states "all those troopers who at the end of the third Game Round are inside the Exclusion Zone, or inside a Deployment Zone/ Dead Zone lacking an Active Heating Unit, must be considered as Killed by the enemy."

So we are at the beginning of the third and last game round, if the first active player starts his game turn in Retreat!, second active player does not have a chance to play his game turn because the match ends at the end of the first active player game turn due to Retreat! rule kicking in End of Mission condition
"If one of the players starts his Active Turn in a Retreat! situation, the game will end at the end of that Turn."

Does Killer Cold trigger? Or the end of the third game round does not take place because at the end of first active player turn the match ends?

Which sequence?

first active player game turn > Retreat! > end of first active player game turn > end of match

or

first active player game turn > Retreat! > end of first active player game turn > end of the third game round > killer cold rule kicks in > end of match​

I perused through the books and wiki but I did not find anywhere rules that define the game round ending conditions enough neatly to solve this. All of this could work for any other mission that had some 3rd game round end effects.

Thanks all

 

Thanks, could you be so kind to link the source?
I know it is maybe bothersome to do and impolite to ask by me, but it will cut short any in game quarrel :D