There seems to be a flash fare war brewing over the Atlantic. AA and BA were advertising Queen’s Jubilee two day sale and soon other carriers were matching as well. The last day to book these is today 17th of May.
You can now find airfares to London on Virgin Atlantic, Air Canada, United Airlines, Delta, Air France, American Airlines, Iberia, and British Airways and probably on few others as well for less than $2K return in business class.
Most of these fares have relatively tight outbound window from North America to Europe, but the return can happen within the ticket validity/fare rules.
These $2K fares out from the eastern seaboard are not that common during holiday periods. They are, however, rare from the west coast.