Hello Vasavi,

It would be tough to tell you about this now as officially there is nothing about it, Last year NEET PG  revised cutoff was announced on 27th April, 2018.

The cutoff revise in that case if the number of candidates who have qualified the exam fall short of the number required in a respective category, then the Central Government in consultation with the Medical Council of India can lower the NEET PG 2019 cut off.

Good Luck!

wen will they release the cutoff marks  usually? how much marks can it be decreased?

Yes , the neet pg will be revised.