Jagdish;
You may be right; we can not fully believe whatever our lawyer says. In my case, too, lawyer never told me that they are applying for CP. But after when I ask them, they said that they always do this due to the fact that, then, both options remain open for client ( CP and I-485).
Also, more complications in my case is that when I applied for I-485, in Jan 01, my H1 was expired ( Nov. 00) and I had applied for H1 extension ( Sept. 00). I have sent H1 ext. receipt along with my papers but could not sent approval notice since it was not approved at that time. It got approved after 15 days. My lawyer said it would not be a problem , but now I am thinking that may be reason for delay and may be RFE. Same is true for H4 ext. in case of my wife and kid.