At the Hearing before the Senate Finance Committee on 2/14/2013, Mr. Cohen from CCIIO said that HHS would be releasing final regs on EHB's (those regs came out this week, by the way), and then insurance companies can make final design changes to their plans. Then in March and April, insurance companies will send those plans and the rates to the govt for approval, and in July the approvals should be finished.
I didn't mean anything quite that formal, just that the carriers have people that are very skilled at costing the plan designs, and have had ample time to get within a couple of points of what the cost per insured will be, etc. and have certainly passed that info. on to the Gov. by now.
I don't think the "final" regs should create sticker shock for the White House. Not after all this time has passed.