Calendar alarm time set on OS X different on iOS

What about icloud ? When you troubleshoot icloud issues, icloud has to get info from one of your devices. if cloud syncs with the phone - bug may be on the Mac and opposite. If the bug is on the phone - give apple phone support a call and Mac same with desktop support. Now they may try to play with your stuff and find it is not a bug, but does sound like one to me.

"iCloud can't use localisation and traveling time"

No idea what you are talking about right now, sorry. Sentence is not making sense. It is not center, it is server.

cool. now how do you setup address, say you want to go to lunch in Paris (France)? Step by step. And when alarm sounds does calendar use your time zone, Paris time zone, phone time zone or Mac. Or does it use the time zone that you setup on icloud.com when you logged in first time?

You are creating too many variables for me and you to understand. We are talking first about creating event, right. Imagine that you do not have to go or setup alarm. Just an event = lunch, diner, etc. Events sync = correct or not?

Then you creating complication Alert/alarm - does that work?

Then you creating walk time complication - does that work.

At what time it stops working?

Cause so far it sounds like you phone understands locations - since it is moving, Mac does not, may be cause it is stationary?

But in any event check one by one.

And since you phone works with icloud and your Mac does not, why don't you take your question to another part of icloud forum- icloud on the mac?

They actually better at that then me. May be we are missing some setting on the Mac ...

iCloud on my Mac

That is an excellent isolation.

So it appears that when event is not created on the phone - phone is not getting proper info about location. Lets verify that one more time by setting such an appointment not on the mac itself, but in icloud.com and if that is going to be off we will know it is the phone.

Once you confirm that you can try couple things, like turning automatic time to off in settings, verifying location accuracy on the phone and may be for good measure resetting all settings on the phone.

Similar issue.

When I set alarms on my Macbook Pro they are different on my iPhone... often by 1 or 2 hours...

and sometimes by other odd times like 1 day & 15 hours? ***?

The only way I can insure accuracy is to set them (or correct them) directly on my iPhone.

Bummer because it's nice to be able to set them on the computer.

I've always had issues with syncing between devices and been going on so long (well over a decade) that frankly I don't think it will ever change.
It's just not a priority for them.