Seems this guy is correct to some extent. I was fed up with the low payment of old contracts. New contracts bought in January did not help either. But, contracts after the new rate is established, seems to be paying really well. I'll be reporting here week on week basis. Already 2 week have passed and they have covered a lot. I think old contracts were on some old miner which are not performing well anymore. They might have got some new miner and established this new rate for those and hence paying well. This is a wild guess though... finger crossed.