How to performs an AC analysis when use Hspice

Hi all: I am a freshman to design OPA. Now I have a problem when I simulate the AC charactor of the full differential OPA.

I use switched capacitor as the CMFB circuit, in order to perform an AC analysis, I use .tran analysis to save the operating point to a file "OPERATINGPOINT.IC", the netlist is:
.SAVE TYPE=NODESET FILE=OPERATINGPOINT.IC LEVEL=ALL TIME=25U
.TRAN 0.1NS 30U START=0U

when I complete the .tran analysis, I start to perform AC analysis, then I use .LOAD statment to load the operating point which save in the file "OPERATINGPOINT.IC", the netlist is:
.LOAD OPERATINGPOINT.IC0
.LIB 'D:\EXERCISE\DESIGNOPA\CSMC06\CSMC.LIB' TT
.AC DEC 10 1 200MEG

But after the AC analysis, I found the operating point is not corrent, and the wave of AC analysis is not correct either! I don't know the reason! why the operating point is not corrent?!

I need help! Help me please, thanx!! The netlist can be found in the attachment.

If u want the operating point exactly the same with that in transient, pls use:

.SAVE TYPE=IC FILE=OPERATINGPOINT.IC LEVEL=ALL TIME=25U

yes, save type should be choosed as IC but not nodeset