Sec 9(3) and sec 9(4) of cgst act rcm implentation

sec 9(3) sec 9(4) of CGST both for RCM

9(3) compulsary RCM  and sec 9(4) with exemption limit

Sec 9(4) to be suspended by Govt up to 31/03/2018  means sec 9(3) yet to be alive 

any one light on it ?   

coz most of confused in it and not charge RCM according to sec 9(3) as most of thought sec was suspended

please  any one focus on it