Oh man, this is something I used to wonder about all the time. Saudi Arabia pretty much sets the date for Eid ul Adha based on their moon sighting since Mecca is there and Hajj happens there. So when Saudi Arabia announces they've seen the crescent moon, a lot of countries just go with their date, especially places like the UAE and even the UK sometimes. But countries like India, Pakistan, and Bangladesh want to actually see the moon themselves on their own horizon before calling it official, which can be a day later or, every once in a while, even two days off.

One year, I remember my friend in Dubai celebrated Eid and I was still waiting for the moon news here in India! It feels kinda weird seeing all the Eid posts online when you haven't started celebrating yet. It's one of those things that really divides opinion: some people think we should all follow Saudi Arabia for unity, and others believe in sticking to local tradition and astronomy. For me, the hype of waiting for that moon announcement with family is part of what makes Eid so fun! But yeah, it can definitely mess up your holiday plans if your cousins are on a different Eid day than you.