There is at least one 744ER converted (maybe more by now). That plane is routinely scheduled to fly QF107/108 so it is a normal rotation. Sometimes substitutions occur which add/subtract from the skybed situation trans-pacific. With high probability the seating will not change (think of the havoc for QF when it does), however mechanicals do happen; not sure now if the replacement is more likely to be old/new (the balance may have tilted to with skybeds).