You can say "Have a nice day" without any problem, but using the phrase "enjoy the next 24 hours" can sound slightly threatening.
@cmconseils

"Day" is indefinite — it basically implies "from this moment until you undertake your next major sleep"

"24 hours" is quite definite.

Factor in "tone", and, yeah, there's an easy case for misinterpreting the latter as a statement of menace.

😄
@ferricoxide @cmconseils
Gonna start using "enjoy this moment until you undertake your next major sleep"
@cmconseils even more so if you wear a watch that's conspicuously counting down
@cmconseils or worse Enjoy the hours you have left till midnight.😈
@temptoetiam @cmconseils Which is the accurate thing to say.
@cmconseils "I wish you much joy until your next loss of consciousness."
@cmconseils Interesting insight. "Have a nice day" gives you the freedom to end the day when ever you like and the next day will show it's own face. "Enjoy the next 24 Hours" sets a hard limit and seems to imply, that you need to renew the option for enjoyable time afterwards.

@cmconseils

"May your continued existence remain free of sorrow until the stroke of midnight."

@cmconseils the day ends when you're at home. 24 hours is not the same

@cmconseils

We used to say, "What's happening?"

Now we just ask, "What happened?"

@cmconseils Such is the case with any unnecessarily specific statement.
@cmconseils It's just one breath at a time however we say it.
@cmconseils the more precise your expression is, the more ominous it'll sound. "I'd like to buy these groceries by these bills that are not counterfeit and which I have gained absolutely leagally, and then I'll go to meet my friend who is alive and whose home hasn't been robbed."
@cmconseils sounds like they've spiked you
@cmconseils i like to leave them with a nice "die slow"

@cmconseils

"Make every second count.".

@cmconseils "Enjoy the next 23 hours and 41 minutes "

@cmconseils
If you want to be really verbose, you could say, "May you savour every moment of the rest of your life."

Bonus points if you can mimic Tony Jay.

@cmconseils - ah, yes. We live in ‘Interesting Times’.
@cmconseils Yeah! And why is "good night" fine, but not "hope you make it till morning"??

@cmconseils The other day I learned the parting idiom "mind how you go" and found it somewhat concerning.

Only later did I realize it was basically the same as the familiar "take care".

(This has made me slightly less annoyed at people who tell me to "bike safe".)

@varx "take care" must be just as efficient as "calm down" which has never actually calmed anyone down.
@cmconseils
@cmconseils 24 hours is too much of a wish. How about "I hope you do well ere the clock strokes midnight next".
@cmconseils Similarly, there's a big difference between a "butt dial" and a "booty call". And of course "Forgive me father, for I have sinned" vs "Sorry daddy, I've been naughty".
@cmconseils @rmondello Well, you can always go with “have a good one”, leaving the units completely unspecified.

@cmconseils oddly specificity can be ominous, as you are implying something will happen at a specific moment (not in your control).

Well op, enjoy your next 2 hours and 22 minutes, I have a toot scheduled

@cmconseils

My favorite description of the difference between east coast and west coast North American culture:

In Los Angeles, someone will say "have a nice day" when they mean "fuck you".

In New York, someone will say "fuck you" when they mean "have a nice day".

@cmconseils there's a sign at the end of the queue at my local supermarket that just says "you're next" - I don't need that level of menace when I'm just trying to buy a bag of liquorice toffees and some chocolate coated peanuts.
@cmconseils Suddenly has new meaning as "24" star Kiefer Sutherland has been arrested...
@cmconseils Am I weird because I'm more concerned that unless you say that at 12PM your nice day wishing will spill out into the next day ?