Yes, I have to agree - this is somewhat weird behaviour. It doesn’t make much sense to me to have such a (relatively) short window of time for the first move to be played in correspondence tournaments where the main time might easily be 30 days or more.
If I’m running a face-to-face tournament, as long as a player has checked in with me that morning, I will start their clock running at the start of the round. I don’t suddenly declare the game over after only a fraction of that player’s main time has elapsed - their opponent needs to wait for the clock to run out main time and byo-yomi to claim the win. A player should be free to use their main time however they want.
I don’t see any mention of a separate timer in the site help files (or anything about disqualification either, for that matter).
Oh well…sorry @signius, had I known this I might not have chosen to start the tournament right on New Year’s Day. My apologies.