Now coming to your question, yes, Kerala is celebrating Eid 2018 on Friday. And so are many people in parts of South India. The rest of the country – states in North – are scheduled to celebrate this festival on Saturday. The reason is same what I explained earlier. A leading body of a sect in South announced that they saw the crescent moon on Thursday evening. Their followers listened to them and are celebrating Eid 2018 on Friday, irrespective of whether or not they agree with them.
On the other hand, Shahi Imam of Jama Masjid Syed Ahmed Bukhari announced that moon sighting committee couldn’t find the crescent on Thursday evening, so the Eid celebration will happen on Saturday. So those who follow them will be celebrating Eid 2018 on Saturday. Plus, a lot also depends on when people of Saudi Arabia is concluding Ramadan. In India, due to the time difference, we usually celebrate Eid a day after them; they are celebrating on Friday, which makes Saturday ‘The Day’ for us.
Hope this answered your question.