As per recent G.O. No. 8912-F(J) dated 01.11.12, the amount of subscription may be
a) enhanced twice at any time during the course of the financial year.
b) reduced once at any time during the course of the financial year.
Sorry, I have no such coppy. But i read it in some news papers. It also written there that the central govt officer who signed the order has retired in that particular date which is most probably 30.11.12.
As you stated in your post that according to some news published in newspaper about the increase in contribution; Mr Roy & myself still looking for the news link here. Please provide the epaper link of the news.