It's true that, in the past, it was recommended to send greetings before January 15 to be sure that they arrived before February 1, which would have been understood as clumsy or impolite. Indeed, at the time of paper mail, La Poste was overwhelmed, which caused delays.
But all these rules of politeness are disappearing: a shame because they contributed to the unity of society.
Years ago, I sent dozens of greeting cards but, by removing people from my list who didn't respond to me, I no longer send them at all except to a few friends in the UK.
