For the First Class part of the fare sale, most fares from East Coast and Midwest Gateways range between $4800 & $5200 while West Coast gateways run in the $5700 to $5900 range.
To take advantage of the First Class deal, you need to depart between December 18 and January 1. Return flights can take plus until March 31. Keep in mind there are a few blackout dates right around Christmas. The best fares are usually available for travel between Monday and Thursday.
The Business Class sale runs for the identical periods and features fares as low as $2800 from the East Coast, and ranges up to the $3700 range for West Coast departures. Like with the First Class sale, the fares are openly available through the end of March, with only a small black out window around Christmas.