Trying to clarify about upgrading TO business class.
The terms state only one-cabin upgrade is allowed and there is no upgrade from coach to PE, but lists several economy fare classes that are eligible. I assume that means you can only upgrade from PE to Business, or from Coach to Business on flights that don't offer PE?
Therefore, for an upgrade into business on a 4-class plane, you'd therefore need to buy PE in G or E (but not N), correct?