No, in Danish the “half five” part means the same as “half past 4” on the clock: 4.5.

Then the part that most people omit nowadays, sindstyvende, means times 20.

(Half past 4) times 20 = 90.

I used to get a notification every year for some dude who had posted on reddit that he was alone on his birthday one year. He stopped replying several years ago, but I still messaged him each year at the prompt of remindme. So that’s also a use case.