I have a caffeine double standard.
Scenario 1: During Sunday-Thursday, when I have work the next morning, my last coffee will be around 15:00.
Scenario 2: If I’m on holiday, or say at a wedding, my last coffee could be after midnight. An espresso at the end of a meal, for example.
In scenario 1, I’m afraid of missing sleep.
In scenario 2, I’m less concerned.
Ironically, I’ve never had a problem with caffeine in scenario 2. But I have had problems with scenario 1 if I have a coffee too late in the afternoon.