What are they supposed to use instead? "Starting in Q3/H2"?
What's wrong with using a calendar date like may the 1st? I know that there are other calendars too. But is more manageable IMO.
Usually it's because they want to keep it vague because the exact date (or even month) hasn't been set yet.
- use "second half of ", "begin of", 3 quartal of, etc.
- or a specific month if they want to be more precise
also for western focused announcements they also use "holliday session" as their tends to be a holliday session in most countries in both summer and winter (through their start differs _a lot_, but it tends to just work out if you release early enough)
And they sometimes use their internal fiscal year, which doesn't align with the calendar year. So sometimes, when they speak of the "fourth quarter" of an year they are talking about the beginning of the next year, or in the opposite direction, they might speak of the "first quarter" of an year but they're talking about the end of the preceding year.
That is winter in the southern hemisphere.
I'm amazed at the need to have to explain this to a grown adult: https://spaceplace.nasa.gov/seasons/en/
Classic example!
In the US, people will normally assume you are talking about Christmas holidays. In Blighty, people will assume summer holidays.