Officially there is no any such kind of notification so I would suggest you to prefer only the official website to get the updated information.

Good Luck!

NEET 2018 that took place on 6th May was held by CBSE. Now, the NTA (National Testing Agency) might conduct the test in December 2018, for the academic year 2019. This is as per recent newpaper articles, links to which you can find below:

Https://www.financialexpress.com/education-2/jee-mains-neet-to-be-held-again-by-nta-in-december-2018-here-is-what-you-should-know/1210378/

Http://www.dnaindia.com/mumbai/report-jee-mains-neet-to-be-conducted-twice-a-year-first-test-in-december-2018-all-you-need-to-know-2626672

But since there is no confirmation from the government as yet, I highly suggest you keep checking about it on a regular basis. 

Good Luck!