Why is that everyone performs Hajj at the same time, but when it comes to other holy days e.g. Shab-e-baraat, lailatul qadr, Eid-ul-fitr, Eid ul Adha we differ?
Where, why and when did the Hijri Calender go wrong? Why can’t we follow one? It’s very upsetting when you celebrate these holy events on different days to other muslims. It gets to me when when you have celebrated Eid-ul-Fitr and your relatives/family back in pakistan have yet got another two fasts to complete of Ramadhan.
Haj is a local event so you follow the local calendar when you are in the city of Makkah. That is why, for Haj, it does not matter if Zil-Haj started in Karachi on a different day than Mekkah
For moon sighting (hence Ramadhan and Eid-ul-Fitr) , there are three school of thoughts.
Visual sighting with in the country
Following scientific calendar
Following Saudi Arabia sighting no matter where you are in the whole world
Every school of thought have their set of Hadees and Quarnic reference to support their practice.